Composition comprising torasemide and baclofen for treating neurological disorders

ABSTRACT

The present invention relates to compositions and methods for the treatment of neurological disorders related to glutamate excitotoxicity and Amyloid β toxicity. More specifically, the present invention relates to novel combinatorial therapies of multiple sclerosis, Alzheimer&#39;s disease, Alzheimer&#39;s disease-related disorders, amyotrophic lateral sclerosis, Parkinson&#39;s disease, Huntington&#39;s disease, neuropathic pain, alcoholic neuropathy, alcoholism or alcohol withdrawal, or spinal cord injury.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the U.S. national stage application of International Patent Application No. PCT/EP2014/068494, filed Sep. 1, 2014, which is a continuation-in-part of U.S. Ser. No. 14/014,650, filed Aug. 30, 2013, which is a continuation-in-part of PCT/EP2012/053565, filed Mar. 1, 2012, which claims priority from U.S. Ser. No. 61/468,658, filed Mar. 29, 2011.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the U.S. national stage application of International Patent Application No. PCT/EP2014/068494, filed Sep. 1, 2014, which is a continuation-in-part of U.S. Ser. No. 14/014,650, filed Aug. 30, 2013, which is a continuation-in-part of PCT/EP2012/053565, filed Mar. 1, 2012, which claims priority from U.S. Ser. No. 61/468,658, filed Mar. 29, 2011.

FIELD OF THE INVENTION

The present invention relates to compositions and methods for the treatment of neurological diseases and disorders. More particularly, this invention relates to novel combinatorial therapies for such diseases, including Alzheimer's and related diseases, multiple sclerosis, amyotrophic lateral sclerosis, Parkinson's disease, neuropathies, alcoholism, alcohol withdrawal, Huntington's disease and spinal cord injury.

BACKGROUND OF THE INVENTION

Alzheimer's disease (AD) is the prototypical cortical dementia, characterized by memory deficit together with dysphasia (language disorder in which there is an impairment of speech and comprehension of speech), dyspraxia (disability to coordinate and perform certain purposeful movements and gestures in the absence of motor or sensory impairments) and agnosia (ability to recognize objects, persons, sounds, shapes, or smells) attributable to involvement of the cortical association areas (1-4).

AD is at present the most common cause of dementia. It is clinically characterized by a global decline of cognitive function that progresses slowly and leaves end-stage patients bound to bed, incontinent and dependent on custodial care. Death occurs, on average, 9 years after diagnosis (5).

The incidence rate of AD increases dramatically with age. United Nations population projections estimate that the number of people older than 80 years will approach 370 million by the year 2050. Currently, it is estimated that 50% of people older than 85 years are afflicted with AD. Therefore, more than 100 million people worldwide will suffer from dementia in 50 years. The vast number of people requiring constant care and other services will severely affect medical, monetary and human resources (6). Memory impairment is the early feature of the disease and involves episodic memory (memory for day-today events). Semantic memory (memory for verbal and visual meaning) is involved later in the disease. The pathological hallmark of AD includes amyloid plaques containing beta-amyloid (Abeta), neurofibrillary tangles (NFT) containing Tau and neuronal and synaptic dysfunction and loss (7-9). For the last decade, two major hypotheses on the cause of AD have been proposed: the “amyloid cascade hypothesis”, which states that the neurodegenerative process is a series of events triggered by the abnormal processing of the Amyloid Precursor Protein (APP) (10), and the “neuronal cytoskeletal degeneration hypothesis” (11), which proposes that cytoskeletal changes are the triggering events. The most widely accepted theory explaining AD progression remains the amyloid cascade hypothesis (12-14) and AD researchers have mainly focused on determining the mechanisms underlying the toxicity associated with Abeta proteins. Microvascular permeability and remodeling, aberrant angiogenesis and blood-brain barrier breakdown have been identified as key events contributing to the APP toxicity in the amyloid cascade (15). On the contrary, Tau protein has received much less attention from the pharmaceutical industry than amyloid, because of both fundamental and practical concerns. Moreover, synaptic density change is the pathological lesion that better correlates with cognitive impairment than the two others.

Studies have revealed that the amyloid pathology appears to progress in a neurotransmitter-specific manner where the cholinergic terminals appear most vulnerable, followed by the glutamatergic terminals and finally by the GABAergic terminals (9). Glutamate is the most abundant excitatory neurotransmitter in the mammalian nervous system. Under pathological conditions, its abnormal accumulation in the synaptic cleft leads to glutamate receptor overactivation (16). Abnormal accumulation of glutamate in the synaptic cleft leads to the overactivation of glutamate receptors that results in pathological processes and finally in neuronal cell death. This process, named excitotoxicity, is commonly observed in neuronal tissues during acute and chronic neurological disorders.

It is becoming evident that excitotoxicity is involved in the pathogenesis of multiple disorders of various etiology, such as spinal cord injury, stroke, traumatic brain injury, hearing loss, alcoholism and alcohol withdrawal, alcoholic neuropathy, and neuropathic pain as well as neurodegenerative diseases such as multiple sclerosis, Alzheimer's disease, amyotrophic lateral sclerosis, Parkinson's disease, and Huntington's disease (17-19). The development of efficient treatment for these diseases remains a major public health issue due to their incidence as well as lack of curative treatments.

NMDAR antagonists that target various sites of this receptor have been tested to counteract excitotoxicity. Uncompetitive NMDAR antagonists target the ion channel pore, thus reducing calcium entry into postsynaptic neurons. Some of them reached approval status. For example, Memantine is currently approved in moderate to severe Alzheimer's disease. It is clinically tested in other indications that include a component of excitotoxicity, such as alcohol dependence (phase II), amyotrophic lateral sclerosis (phase III), dementia associated with Parkinson's (Phase II), epilepsy, Huntington's disease (phase IV), multiple sclerosis (phase IV), Parkinson's disease (phase IV) and traumatic brain injury (phase IV). This molecule is, however, of limited benefit to most Alzheimer's disease patients, because it has only modest symptomatic effects. Another approach in limiting excitotoxicity consists of inhibiting the presynaptic release of glutamate. Riluzole, currently approved for amyotrophic lateral sclerosis, showed encouraging results in ischemia and traumatic brain injury models (20-23). It is at present being tested in phase II trials in early multiple sclerosis and Parkinson's disease (does not show any better results than placebo) as well as spinal cord injury. In 1995, the drug reached orphan drug status for the treatment of amyotrophic lateral sclerosis, and in 1996 for the treatment of Huntington's disease.

WO2009/133128, WO2009/133141, WO2009/133142, and WO2011/054759 disclose molecules which can be used in compositions for treating neurological disorders.

Despite active research in this area, there is still a need for alternative or improved, efficient therapies for neurological disorders, and, in particular, neurological disorders which are related to glutamate and/or amyloid beta toxicity. The present invention provides new treatments for such neurological diseases of the central nervous system (CNS) and the peripheral nervous system (PNS).

SUMMARY OF INVENTION

An object of the present invention is to provide new therapeutic approaches for treating neurological disorders.

The invention stems, inter alia, from the unexpected discovery by the inventors that Torasemide, Trimetazidine, Mexiletine, Bromocriptine, Ifenprodil and Moxifloxacin, alone or in combination, represent new and effective therapies for the treatment of neurological disorders.

The invention therefore provides novel compositions and methods for treating neurological disorders, particularly AD and related disorders, multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), Parkinson's disease (PD), neuropathies (for instance, neuropathic pain or alcoholic neuropathy), alcoholism or alcohol withdrawal, damage to the peripheral nervous system, Huntington's disease (HD) and spinal cord injury.

More particularly, the invention relates to a composition, for use in the treatment of a neurological disorder, comprising at least Torasemide, Trimetazidine, Mexiletine, Ifenprodil, Moxifloxacin or Bromocriptine, or a salt, prodrug, derivative, or sustained-release formulation thereof.

A further object of the present invention relates to a composition comprising at least one first compound selected from the group consisting of Torasemide, Trimetazidine, Mexiletine, Ifenprodil, Moxifloxacin, and Bromocriptine, or a salt, prodrug, derivative of any chemical purity, or sustained-release formulation thereof, in combination with at least one second compound distinct from said first compound, selected from Sulfisoxazole, Methimazole, Prilocaine, Dyphylline, Quinacrine, Carbenoxolone, Acamprosate, Aminocaproic acid, Baclofen, Cabergoline, Diethylcarbamazine, Cinacalcet, Cinnarizine, Eplerenone, Fenoldopam, Leflunomide, Levosimendan, Sulodexide, Terbinafine, Zonisamide, Etomidate, Phenformin, Trimetazidine, Mexiletine, Bromocriptine, Ifenprodil, Torasemide, and Moxifloxacin, or salts, prodrugs, derivatives of any chemical purity, or sustained-release formulations thereof, for simultaneous, separate or sequential administration.

A further object of the present invention relates to a composition, for use in the treatment of a neurological disorder, comprising at least one first compound selected from the group consisting of Torasemide, Trimetazidine, Mexiletine, Ifenprodil, Moxifloxacin, and Bromocriptine, or salts, prodrugs, derivatives of any chemical purity, or sustained-release formulations thereof, in combination with at least one second compound distinct from said first compound, selected from Sulfisoxazole, Methimazole, Prilocaine, Dyphylline, Quinacrine, Carbenoxolone, Acamprosate, Aminocaproic acid, Baclofen, Cabergoline, Diethylcarbamazine, Cinacalcet, Cinnarizine, Eplerenone, Fenoldopam, Leflunomide, Levosimendan, Sulodexide, Terbinafine, Zonisamide, Etomidate, Phenformin, Trimetazidine, Mexiletine, Bromocriptine, Ifenprodil, Torasemide, and Moxifloxacin, or salts, prodrugs, derivatives of any chemical purity, or sustained-release formulations thereof, for simultaneous, separate or sequential administration.

The present invention also relates to a composition comprising at least one first compound selected from the group consisting of Torasemide, Trimetazidine, Mexiletine, Ifenprodil, Moxifloxacin and Bromocriptine, or salt(s), prodrug(s), derivative(s) of any chemical purity, or sustained-release formulation(s) thereof, in combination with at least one second compound distinct from said first compound, selected from Sulfisoxazole, Methimazole, Prilocaine, Dyphylline, Quinacrine, Carbenoxolone, Acamprosate, Aminocaproic acid, Baclofen, Cabergoline, Diethylcarbamazine, Cinacalcet, Cinnarizine, Eplerenone, Fenoldopam, Leflunomide, Levosimendan, Sulodexide, Terbinafine, Zonisamide, Etomidate, Phenformin, Trimetazidine, Mexiletine, Bromocriptine, Ifenprodil, Torasemide, and Moxifloxacin, or salt(s), prodrug(s), derivative(s) of any chemical purity, or sustained-release formulation(s) thereof, and a pharmaceutically acceptable excipient, for simultaneous, separate or sequential administration.

Most preferred drug compositions comprise 1, 2, 3, 4 or 5 distinct drugs, even more preferably 2, 3 or 4. Furthermore, the above drug compositions may also be used in further combination with one or several additional drugs or treatments beneficial to subjects with a neurological disorder.

The invention also relates to a method of treating a neurological disorder, the method comprising administering to a subject in need thereof a drug or composition as disclosed above.

A further object of this invention relates to a method of treating a neurological disorder, the method comprising simultaneously, separately or sequentially administering to a subject in need thereof a drug combination as disclosed above.

A further object of this invention relates to the use of at least one compound selected from the group consisting of Torasemide, Trimetazidine, Mexiletine, Ifenprodil, Bromocriptine and Moxifloxacin, or salt(s), prodrug(s), derivative(s) of any chemical purity, or sustained-release formulation(s) thereof, for the manufacture of a medicament for the treatment of a neurological disorder.

A further object of this invention relates to the use of drug combinations disclosed above for the manufacture of a medicament for the treatment of a neurological disorder.

The invention may be used in any mammalian subject, particularly a human subject, at any stage of the disease.

BRIEF DESCRIPTION OF THE FIGURES

For FIGS. 1 to 27, *: p<0.05: significantly different from control (no intoxication); “ns”: no significant effect (ANOVA+Dunnett's Post-Hoc test)

FIG. 1: Effect of selected drugs pre-treatment against human Aβ₁₋₄₂ injury in HBMEC. A) Validation of the experimental model used for drug screening: 1 hr of VEGF pre-treatment at 10 nM significantly protected the capillary network from this amyloid injury (+70% of capillary network compared to amyloid intoxication). The intoxication is significantly prevented by Torasemide (B) and Bromocriptine (C) at doses as low as of 400 nM and 3.2 nM, respectively, whereas no or a weaker effect is noticed for upper and lower doses.

: p<0.05: significantly different from Amyloid intoxication.

FIG. 2: Effect of selected drugs pre-treatment on LDH release in human Aβ₁₋₄₂ toxicity assays on rat primary cortical cells. A) Validation of the experimental model used for drug screening: 1 hr of Estradiol (150 ng/ml) pre-treatment significantly protected the neurons from this amyloid injury (−70%), which is considered a positive control for neuroprotection. For all experiments, Aβ₁₋₄₂ produces significant intoxication compared to vehicle-treated neurons. The intoxication is significantly prevented by Bromocriptine (40 nM, −29%) (B), Trimetazidine (40 nM, −94%) (C), Ifenprodil (600 nM, −94%) (D), Mexiletine (3.2 nM, −73%) (E), and Moxifloxacin (20 nM, −63%) (F). Note that for other drug concentrations, no or a weaker effect is noticed for upper and lower doses.

: p<0.05: significantly different from Aβ₁₋₄₂ intoxication.

FIG. 3: Effect of Baclofen and Torasemide combination therapy on the total length of capillary network in beta-amyloid intoxicated HBMEC cultures. The aggregated human amyloid peptide (Aβ₁₋₄₂ 2.5 μM) produces significant intoxication, above 40%, compared to vehicle-treated cells. This intoxication is significantly prevented by the combination of Baclofen and Torasemide (A), whereas, at those concentrations, Baclofen (B) and Torasemide (C) alone have no significant effect on intoxication.

: p<0.05, significantly different from Aβ₁₋₄₂ intoxication.

FIG. 4: Effect of Sulfisoxazole and Torasemide combination therapy on the total length of capillary network in beta-amyloid intoxicated HBMEC cultures. The aggregated human amyloid peptide (Aβ₁₋₄₂ 2.5 μM) produces significant intoxication, above 40%, compared to vehicle-treated cells. This intoxication is significantly prevented by the combination of Sulfisoxazole and Torasemide (A), whereas, at those concentrations, Sulfisoxazole (B) and Torasemide (C) alone have no significant effect on intoxication.

: p<0.05, significantly different from Aβ₁₋₄₂ intoxication.

FIG. 5: Effect of Eplerenone and Torasemide combination therapy on the total length of capillary network in beta-amyloid intoxicated HBMEC cultures. The aggregated human amyloid peptide (Aβ₁₋₄₂ 2.5 μM) produces significant intoxication, above 40%, compared to vehicle-treated cells. This intoxication is significantly prevented by the combination of Eplerenone and Torasemide (A), whereas, at those concentrations, Torasemide (B) and Eplerenone (C) alone have no significant effect on intoxication.

: p<0.05, significantly different from Aβ₁₋₄₂ intoxication.

FIG. 6: Effect of Bromocriptine and Sulfisoxazole combination therapy on the total length of capillary network in beta-amyloid intoxicated HBMEC cultures. The aggregated human amyloid peptide (Aβ₁₋₄₂ 2.5 μM) produces significant intoxication, above 40%, compared to vehicle-treated cells. This intoxication is significantly prevented by the combination of Bromocriptine and Sulfisoxazole (A), whereas, at those concentrations, Bromocriptine (B) and Sulfisoxazole (C) alone have no significant effect on intoxication.

: p<0.05, significantly different from Aβ₁₋₄₂ intoxication.

FIG. 7: Effect of Acamprosate and Ifenprodil combination therapy on LDH release in human Aβ₁₋₄₂ toxicity on rat primary cortical cells. The aggregated human amyloid peptide (Aβ₁₋₄₂ 10 μM) produces significant intoxication compared to vehicle-treated neurons. This intoxication is significantly prevented by the combination of Acamprosate and Ifenprodil (A), whereas, at those concentrations, Acamprosate (B) and Ifenprodil (C) alone have no significant effect on intoxication.

: p<0.05, significantly different from Aβ₁₋₄₂ intoxication.

FIG. 8: Effect of Baclofen and Mexiletine combination therapy on LDH release in human Aβ₁₋₄₂ toxicity on rat primary cortical cells. The aggregated human amyloid peptide (Aβ₁₋₄₂ 10 μM) produces significant intoxication compared to vehicle-treated neurons. This intoxication is significantly prevented by the combination of Baclofen and Mexiletine (A), whereas, at those concentrations, Baclofen (B) and Mexiletine (C) alone have no significant effect on intoxication.

: p=0.051, different from Aβ₁₋₄₂ intoxication.

FIG. 9: Effect of Baclofen and Trimetazidine combination therapy on LDH release in human Aβ₁₋₄₂ toxicity on rat primary cortical cells. The aggregated human amyloid peptide (Aβ₁₋₄₂ 10 μM) produces significant intoxication compared to vehicle-treated neurons. This intoxication is significantly prevented by the combination of Baclofen and Trimetazidine (A), whereas, at those concentrations, Baclofen (B) and Trimetazidine (C) alone have no significant effect on intoxication.

: p<0.05, significantly different from Aβ₁₋₄₂ intoxication.

FIG. 10: Effect of Cinacalcet and Mexiletine combination therapy on LDH release in human Aβ₁₋₄₂ toxicity on rat primary cortical cells. The aggregated human amyloid peptide (Aβ₁₋₄₂ 10 μM) produces significant intoxication compared to vehicle-treated neurons. This intoxication is significantly prevented by the combination of Cinacalcet and Mexiletine (A), whereas, at those concentrations, Cinacalcet (B) and Mexiletine (C) alone have no significant effect on intoxication.

: p<0.05, significantly different from Aβ₁₋₄₂ intoxication.

FIG. 11: Effect of Cinnarizine and Trimetazidine combination therapy on LDH release in human Aβ₁₋₄₂ toxicity on rat primary cortical cells. The aggregated human amyloid peptide (Aβ₁₋₄₂ 10 μM) produces significant intoxication compared to vehicle-treated neurons. This intoxication is significantly prevented by the combination of Cinnarizine and Trimetazidine (A), whereas, at those concentrations, Cinnarizine (B) and Trimetazidine (C) alone have no significant effect on intoxication.

: p<0.05, significantly different from Aβ₁₋₄₂ intoxication.

FIG. 12: Effect of Trimetazidine and Zonisamide combination therapy on LDH release in human Aβ₁₋₄₂ toxicity on rat primary cortical cells. The aggregated human amyloid peptide (Aβ₁₋₄₂ 10 μM) produces significant intoxication compared to vehicle-treated neurons. This intoxication is significantly prevented by the combination of Trimetazidine and Zonisamide (A), whereas, at those concentrations, Trimetazidine (B) and Zonisamide (C) alone have no significant effect on intoxication.

: p<0.05, significantly different from Aβ₁₋₄₂ intoxication.

FIG. 13: Effect of Terbinafine and Torasemide combination therapy on the total length of capillary network in beta-amyloid intoxicated HBMEC cultures. The aggregated human amyloid peptide (Aβ₁₋₄₂ 2.5 μM) produces significant intoxication, above 40%, compared to vehicle-treated cells. This intoxication is significantly prevented by the combination of Terbinafine and Torasemide (A), whereas, at those concentrations, Terbinafine (B) and Torasemide (C) alone have no significant effect on intoxication.

: p<0.05, significantly different from Aβ₁₋₄₂ intoxication.

FIG. 14: Effect of Cinacalcet and Mexiletine combination therapy on the total length of capillary network in beta-amyloid intoxicated HBMEC cultures. The aggregated human amyloid peptide (Aβ₁₋₄₂ 2.5 μM) produces significant intoxication, above 40%, compared to vehicle-treated cells. This intoxication is significantly prevented by the combination of Cinacalcet and Mexiletine (A), whereas, at those concentrations, Cinacalcet (B) and Mexiletine (C) alone have no significant effect on intoxication.

: p<0.05, significantly different from Aβ₁₋₄₂ intoxication.

FIG. 15: Effect of Baclofen and Torasemide combination therapy on LDH release in human Aβ₁₋₄₂ toxicity on rat primary cortical cells. The aggregated human amyloid peptide (Aβ₁₋₄₂ 10 μM) produces significant intoxication compared to vehicle-treated neurons. This intoxication is significantly prevented by the combination of Baclofen and Torasemide, whereas, at those concentrations, Baclofen and Torasemide alone have no significant effect on intoxication.

: p<0.05, significantly different from Aβ₁₋₄₂ intoxication.

FIG. 16: Effect of Torasemide and Sulfisoxazole combination therapy on LDH release in human Aβ₁₋₄₂ toxicity on rat primary cortical cells. The aggregated human amyloid peptide (Aβ₁₋₄₂ 10 μM) produces significant intoxication compared to vehicle-treated neurons. This intoxication is significantly prevented by the combination of Sulfisoxazole and Torasemide (A), whereas, at those concentrations, Torasemide (B) and Sulfisoxazole (C) alone have no significant effect on intoxication.

: p<0.05, significantly different from Aβ₁₋₄₂ intoxication.

FIG. 17: Effect of Moxifloxacin and Trimetazidine combination therapy on LDH release in human Aβ₁₋₄₂ toxicity on rat primary cortical cells. The aggregated human amyloid peptide (Aβ₁₋₄₂ 10 μM) produces significant intoxication compared to vehicle-treated neurons. This intoxication is significantly prevented by the combination of Moxifloxacin and Trimetazidine (A). Adjunction of Moxifloxacin allows an increase of 100% of the effect observed for Trimetazidine (C) alone, whereas, at the same concentration, Moxifloxacin (B) alone has no significant effect on intoxication.

: p<0.05, significantly different from Aβ₁₋₄₂ intoxication.

FIG. 18: Effect of Moxifloxacin and Baclofen combination therapy on LDH release in human Aβ₁₋₄₂ toxicity on rat primary cortical cells. The aggregated human amyloid peptide (Aβ₁₋₄₂ 10 μM) produces significant intoxication compared to vehicle-treated neurons. This intoxication is significantly prevented by the combination of Moxifloxacin and Baclofen (A), whereas, at those concentrations, Moxifloxacin (B) and Baclofen (C) alone have no significant effect on intoxication.

: p<0.05, significantly different from Aβ₁₋₄₂ intoxication.

FIG. 19: Effect of Moxifloxacin and Cinacalcet combination therapy on LDH release in human Aβ₁₋₄₂ toxicity on rat primary cortical cells. The aggregated human amyloid peptide (Aβ₁₋₄₂ 10 μM) produces significant intoxication compared to vehicle-treated neurons. This intoxication is significantly prevented by the combination of Moxifloxacin and Cinacalcet (A), whereas, at those concentrations, Moxifloxacin (B) and Cinacalcet (C) alone have no significant effect on intoxication.

: p<0.05, significantly different from Aβ₁₋₄₂ intoxication.

FIG. 20: Effect of Moxifloxacin and Zonisamide combination therapy on LDH release in human Aβ₁₋₄₂ toxicity on rat primary cortical cells. The aggregated human amyloid peptide (Aβ₁₋₄₂ 10 μM) produces significant intoxication compared to vehicle-treated neurons. This intoxication is significantly prevented by the combination of Moxifloxacin and Zonisamide (A). Adjunction of Moxifloxacin allows an increase of 81% of the effect observed for Zonisamide (C) alone, whereas, at the same concentration, Moxifloxacin (B) alone has no significant effect on intoxication.

: p<0.05, significantly different from Aβ₁₋₄₂ intoxication.

FIG. 21: Effect of Moxifloxacin and Sulfisoxazole combination therapy on LDH release in human Aβ₁₋₄₂ toxicity on rat primary cortical cells. The aggregated human amyloid peptide (Aβ₁₋₄₂ 10 μM) produces significant intoxication compared to vehicle-treated neurons. This intoxication is significantly prevented by the combination of Moxifloxacin and Sulfisoxazole (A), whereas, at those concentrations, Moxifloxacin (B) and Sulfisoxazole (C) alone have no significant effect on intoxication.

: p<0.05, significantly different from Aβ₁₋₄₂ intoxication.

FIG. 22: Effect of Mexiletine (MEX) and Ifenprodil (IFN) combination therapy on LDH release in human Aβ₁₋₄₂ toxicity on rat primary cortical cells. The aggregated human amyloid peptide (Aβ₁₋₄₂ 10 μM) produces significant intoxication compared to vehicle-treated neurons. This intoxication is significantly prevented by the combination of Mexiletine (25.6 pM) and Ifenprodil (24 nM), whereas, at those concentrations, Mexiletine and Ifenprodil alone have no significant effect on intoxication.

: p<0.0572, significantly different from Aβ₁₋₄₂ intoxication.

FIG. 23: Effect of Baclofen (BCL) and Torasemide (TOR) combination therapy on the total length of neurite network in beta-amyloid intoxicated cortical neurons. The human amyloid peptide (Aβ₁₋₄₂ 2.5 μM) produces significant intoxication, above 15%, compared to vehicle-treated cells. This intoxication is significantly prevented by the combination of Torasemide and Baclofen; furthermore, this combination allows an enhancement of neurite growth.

: p<0.05, significantly different from Aβ₁₋₄₂ intoxication.

FIG. 24: Effect of Cinacalcet and Mexiletine combination therapy against glutamate toxicity on neuronal cortical cells. The glutamate intoxication is significantly prevented by the combination of Cinacalcet (64 pM) and Mexiletine (25.6 pM), whereas, at those concentrations, Cinacalcet and Mexiletine alone have no significant effect on intoxication.

: p<0.001, significantly different from glutamate intoxication; (ANOVA+Dunnett Post-Hoc test).

FIG. 25: Effect of Sulfisoxazole and Torasemide combination therapy against glutamate toxicity on neuronal cortical cells. The glutamate intoxication is significantly prevented by the combination of Sulfisoxazole (6.8 nM) and Torasemide (400 nM), whereas, at those concentrations, Sulfisoxazole and Torasemide alone have no significant effect on intoxication.

: p<0.001, significantly different from glutamate intoxication; (ANOVA+Dunnett Post-Hoc test).

FIG. 26: Effect of Torasemide (TOR) pre-treatment on LDH release in human Aβ₁₋₄₂ toxicity assays on rat primary cortical cells. Aβ₁₋₄₂ produces significant intoxication compared to vehicle-treated neurons. The intoxication is significantly prevented by Torasemide (200 nM, −90%). ⋄: p<0.0001: significantly different from Aβ₁₋₄₂ intoxication.

FIG. 27: Comparison of Acamprosate and its derivative Homotaurine pre-treatment on LDH release in human Aβ₁₋₄₂ toxicity assays on rat primary cortical cells. Aβ₁₋₄₂ produces significant intoxication compared to vehicle-treated neurons. The intoxication is equally significantly prevented by Homotaurine and Acamprosate (99%, 8 nM). ⋄: p<0.0001: significantly different from Aβ₁₋₄₂ intoxication.

FIG. 28: Effect of Baclofen (BCL) and Torasemide (TOR) combination on the total length of neurite network in cortical neurons cultured in the absence of toxin. An increase of neurite network length is observed when the Baclofen (400 nM) and Torasemide (80 nM) combination is added in the culture medium; furthermore, this combination allows an enhancement of neurite growth, whereas, at those concentrations, Baclofen and Torasemide alone have no significant (ns) effect on neurite network length. * p<0.005, significantly different from control.

FIG. 29: Effect of Baclofen (BCL) and Torasemide (TOR) combination in promoting nerve regeneration after nerve crush. (A) Animals experiencing nerve injury (nerve crush) treated with the Baclofen-Torasemide combination show a significantly lower latency of CMAP upon stimulation of the injured sciatic nerve at day 7 and day 30 from nerve crush when compared to the sham-operated animals (white bar) or the vehicle-treated animals. (B) Amplitudes of the signal of muscular evoked potentials upon sciatic nerve stimulation are significantly lower in animals experiencing nerve injury when compared to the sham operated animals at both day 7 and day 30 from nerve crush. A significant increase in CMAP amplitude is observed at day 30 from nerve crush for the animals treated with Baclofen (3 mg/kg)-Torasemide (400 μg/kg) (dose 3) bid. *p<0.05; **p<0.001; ***p<0.0001, significantly different from vehicle-treated animals (black bar).

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides new compositions for treating neurological disorders. The invention discloses novel uses of drugs or novel drug combinations which allow an effective correction of such diseases and may be used for patient treatment.

The invention is suited for treating any neurological disorder, whether central or peripheral, particularly disorders wherein amyloid or glutamate excitotoxicity is involved. Specific examples of such disorders include neurodegenerative diseases such as Alzheimer's and related disorders, multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), Parkinson's disease (PD), Huntington's disease (HD), or other neurological disorders like neuropathies (for instance, alcoholic neuropathy or neuropathic pain), alcoholism or alcohol withdrawal and spinal cord injury. “Neuropathies” refers to conditions where nerves of the peripheral nervous system are damaged; this include damages of the peripheral nervous system provoked by genetic factors, inflammatory disease, chemical substances including drugs (e.g., vincristine, oxaliplatin, ethyl alcohol), or a direct physical insult to the nerve. The treatment of neuropathies also includes the treatment of neuropathic pain.

Damage of the peripheral nervous system can be ranked according to the stage of neuronal insult. The invention is suited for treating nerve injuries ranking from neuropraxia (a condition where only the signaling ability of the nerve is impaired) or axonotmesis (injury implying damage to the axons, without impairing the surrounding connective tissues of the nerves) to neurotmesis (injury damaging both axons and surrounding tissues).

Alterations in axons or in surrounding tissues (such as myelin) can be of genetic origin. An example of an inherited neuropathy is the so-called Charcot-Marie-Tooth family of diseases. Charcot-Marie-Tooth diseases are progressive disorders that affect peripheral nerves and are distinguished by the specific gene(s) that is (are) altered. Mutation(s) result in an impairment of axons, which transmit nerve impulses, and/or affect the production of the myelin sheath by Schwann cells, which is implicated in the speed of the transmission of nervous impulses. There are several types (categorized as a function of clinical features) and subtypes of CMT (corresponding to a genetic classification). The CMT types are CMT1, CMT2, CMT3, CMT4, CMT5, CMT6, CMTDI, CMTRI, CMTX. Related peripheral neuropathies include, for example, HNPP (hereditary neuropathy with liability to pressure palsies), severe demyelinating neuropathies DSS (Dejerine-Sottas syndrome), and CHN (congenital hypomyelinating neuropathy). CMT1 (a demyelinating type) and CMT2 (an axonal type) account for around 70% of CMT patients.

The invention is particularly suited for treating AD and related disorders. In the context of this invention, the term “AD-related disorder” includes senile dementia of AD type (SDAT), Lewy body dementia, vascular dementia, mild cognitive impairment (MCI) and age-associated memory impairment (AAMI).

As used herein, “treatment” includes the therapy, prevention, prophylaxis, retardation or reduction of symptoms provoked by or of the causes of the above diseases or disorders. The term treatment includes in particular the control of disease progression and associated symptoms. The term treatment particularly includes i) a protection against the toxicity caused by amyloid beta, or a reduction or retardation of said toxicity, and/or ii) a protection against glutamate excitotoxicity, or a reduction or retardation of said toxicity, in the treated subjects. The term treatment also designates an improvement of cognitive symptoms or a protection of neuronal cells. In relation to neuropathies, the term treatment also includes nerve regeneration, which encompasses remyelination and generation of new neurons, glia, axons, myelin or synapses.

Within the context of this invention, the designation of specific compounds is meant to include not only the specifically named molecules, but also any pharmaceutically acceptable salts, hydrates, derivatives (e.g., ester, ether), isomers, racemates, conjugates, or prodrugs thereof, of any purity.

The term “prodrug” as used herein refers to any functional derivatives (or precursors) of a compound of the present invention which, when administered to a biological system, generate said compound as a result of, e.g., spontaneous chemical reaction(s), enzyme-catalyzed chemical reaction(s), and/or metabolic chemical reaction(s). Prodrugs are usually inactive or less active than the resulting drug and can be used, for example, to improve the physicochemical properties of the drug, to target the drug to a specific tissue, to improve the pharmacokinetic and pharmacodynamic properties of the drug and/or to reduce undesirable side effects. Prodrugs typically have the structure X-drug wherein X is an inert carrier moiety and drug is the active compound, wherein the prodrug is less active than the drug and the drug is released from the carrier in vivo. Some of the common functional groups that are amenable to prodrug design include, but are not limited to, carboxylic, hydroxyl, amine, phosphate/phosphonate and carbonyl groups. Prodrugs typically produced via the modification of these groups include, but are not limited to, esters, carbonates, carbamates, amides and phosphates. Specific technical guidance for the selection of suitable prodrugs is general common knowledge (24-28). Furthermore, the preparation of prodrugs may be performed by conventional methods known by those skilled in the art. Methods which can be used to synthesize other prodrugs are described in numerous reviews on the subject (25; 29-35). For example, Arbaclofen Placarbil is listed in ChemIDplus Advanced database (see Worldwide Website: chem.sis.nlm.nih.gov/chemidplus/) and Arbaclofen Placarbil is a well-known prodrug of Baclofen (36; 43).

The term “derivative” of a compound includes any molecule that is functionally and/or structurally related to said compound, such as an acid, amide, ester, ether, acetylated variant, hydroxylated variant, or alkylated (C1-C6) variant of such a compound. The term derivative also includes structurally related compounds having lost one or more substituent as listed above. For example, Homotaurine is a deacetylated derivative of Acamprosate. Preferred derivatives of a compound are molecules having a substantial degree of similarity to said compound, as determined by known methods. Similar compounds along with their index of similarity to a parent molecule can be found in numerous databases such as PubChem (see Worldwide Website: pubchem.ncbi.nlm.nih.gov/search/) or DrugBank (see Worldwide Web site: drugbank.ca/). In a more preferred embodiment, derivatives should have a Tanimoto similarity index greater than 0.4, preferably greater than 0.5, more preferably greater than 0.6, even more preferably greater than 0.7, with a parent drug. The Tanimoto similarity index is widely used to measure the degree of structural similarity between two molecules. Tanimoto similarity index can be computed by software such as the Small Molecule Subgraph Detector (37-38) available online (see Worldwide Website: ebi.ac.uk/thornton-srv/software/SMSD/). Preferred derivatives should be both structurally and functionally related to a parent compound, i.e., they should also retain at least part of the activity of the parent drug; more preferably, they should have a protective activity against Aβ or glutamate toxicity.

The term derivatives also includes metabolites of a drug, e.g., molecules which result from the (biochemical) modification(s) or processing of said drug after administration to an organism, usually through specialized enzymatic systems, and which display or retain a biological activity of the drug. Metabolites have been disclosed as being responsible for much of the therapeutic action of the parent drug. In a specific embodiment, a “metabolite” as used herein designates a modified or processed drug that retains at least part of the activity of the parent drug, and that preferably has a protective activity against Aβ toxicity or glutamate toxicity. Examples of metabolites include hydroxylated forms of Torasemide resulting from the hepatic metabolism of the drug (DrugBank database (39)).

The term “salt” refers to a pharmaceutically acceptable and relatively non-toxic, inorganic or organic acid addition salt of a compound of the present invention. Pharmaceutical salt formation consists of pairing an acidic, basic or zwitterionic drug molecule with a counterion to create a salt version of the drug. A wide variety of chemical species can be used in neutralization reactions. Pharmaceutically acceptable salts of the invention thus include those obtained by reacting the main compound, functioning as a base, with an inorganic or organic acid to form a salt, for example, salts of acetic acid, nitric acid, tartaric acid, hydrochloric acid, sulfuric acid, phosphoric acid, methanesulfonic acid, camphorsulfonic acid, oxalic acid, maleic acid, succinic acid or citric acid. Pharmaceutically acceptable salts of the invention also include those in which the main compound functions as an acid and is reacted with an appropriate base to form, e.g., sodium, potassium, calcium, magnesium, ammonium, or choline salts. Though most of the salts of a given active principle are bioequivalents, some may have, among other properties, increased solubility or bioavailability. Salt selection is now a common standard operation in the process of drug development, as taught by H. Stahl and C. G. Wermuth in their handbook (40).

The term “combination” or “combinatorial treatment/therapy” designates a treatment wherein at least two or more drugs are co-administered to a subject to cause a biological effect. In a combined therapy according to this invention, the at least two drugs may be administered together or separately, at the same time or sequentially. Also, the at least two drugs may be administered through different routes and protocols. As a result, although they may be formulated together, the drugs of a combination may also be formulated separately.

As disclosed in the examples, Torasemide, Trimetazidine, Mexiletine, Ifenprodil, Bromocriptine and Moxifloxacin have a strong unexpected effect on biological processes involved in neurological disorders. Furthermore, these compounds also showed in vivo a very efficient ability to correct symptoms of such diseases. These molecules, alone or in combination therapies, therefore represent novel approaches for treating neurological disorders, such as Alzheimer's disease, multiple sclerosis, amyotrophic lateral sclerosis, Parkinson's disease, Huntington's disease, neuropathies (for instance, neuropathic pain or alcoholic neuropathy), alcoholism or alcohol withdrawal, and spinal cord injury. Combinations of these drugs with other selected compounds (see Table 2) are particularly advantageous because they produce a surprising and unexpected synergistic effect at dosages where the drugs alone have essentially no effect. Also, because of their efficacy, the herein-disclosed drug combinations can be used at low dosages, which is a further very substantial advantage.

In this regard, in a particular embodiment, the invention relates to a composition for use in the treatment of AD, AD-related disorders, MS, PD, ALS, HD, neuropathies (for instance, neuropathic pain or alcoholic neuropathy), alcoholism or alcohol withdrawal, or spinal cord injury, comprising at least Torasemide, Trimetazidine, Mexiletine, Ifenprodil, Bromocriptine, or Moxifloxacin, or a salt, prodrug, derivative, or sustained-release formulation thereof.

The specific CAS number for each of these compounds is provided in Table 1 below. Table 1 cites also, in a non-limitative way, common salts, racemates, prodrugs, metabolites or derivatives for these compounds used in the compositions of the invention.

TABLE 1 Class or Tanimoto similarity Drug CAS Numbers index Mexiletine and related compounds Mexiletine 31828-71-4; 5370-01-4 6-Hydroxymethylmexiletine 53566-98-6 Metabolite 4-Hydroxymexiletine 53566-99-7 Metabolite 3-Hydroxymexiletine (MHM) 129417-37-4 Metabolite N-Hydroxymexiletine 151636-18-9 Metabolite glucuronide Sulfisoxazole and related compounds Sulfisoxazole 127-69-5; 4299-60-9 N(4)-Acetylsulfisoxazole 4206-74-0 Metabolite Sulfisoxazole acetyl 80-74-0 Prodrug Sulfamethoxazole 723-46-6 0.52 Cinacalcet and related compounds Cinacalcet 226256-56-0; 364782-34-3 Hydrocinnamic acid 501-52-0 Metabolite Torasemide and related compounds Torasemide 56211-40-6; 72810-59-4 Hydroxytorasemide 99300-68-2; 99300-67-1 Metabolites Carboxytorasemide Metabolite Tolbutamide 64-77-7 0.55 Bromocriptine and related compounds Bromocriptine 25614-03-3; 22260-51-1 Ifenprodil and related compounds Ifenprodil 23210-56-2; 23210-58-4

The above molecules may be used alone or, preferably, in combination therapies to provide the most efficient clinical benefit. In this regard, in a preferred embodiment, the invention relates to a composition for use in the treatment of a neurological disorder, preferably AD, AD-related disorders, MS, PD, ALS, HD, neuropathies (for instance, neuropathic pain or alcoholic neuropathy), alcoholism or alcohol withdrawal, or spinal cord injury, comprising any one of the above compounds in combination with at least one distinct compound selected from Sulfisoxazole, Methimazole, Prilocaine, Dyphylline, Quinacrine, Carbenoxolone, Acamprosate, Aminocaproic acid, Baclofen, Cabergoline, Diethylcarbamazine, Cinacalcet, Cinnarizine, Eplerenone, Fenoldopam, Leflunomide, Levosimendan, Sulodexide, Terbinafine, Zonisamide, Etomidate, Phenformin, Trimetazidine, Mexiletine, Ifenprodil, Moxifloxacin, Bromocriptine or Torasemide, or a salt, prodrug, derivative, or sustained-release formulation thereof.

The specific CAS number for each of these additional distinct compounds, different from those of Table 1, is provided in Table 2 below.

TABLE 2 DRUG NAME CAS NUMBER Acamprosate 77337-76-9; 77337-73-6; 107-35-7; 3687-18-1 Aminocaproic Acid 60-32-2 Baclofen 1134-47-0; 66514-99-6; 69308-37-8; 70206-22-3; 63701-56-4; 63701-55-3; 847353-30-4 Cabergoline 81409-90-7 Carbenoxolone 5697-56-3 or 7421-40-1 Cinnarizine 298-57-7 Diethylcarbamazine 90-89-1 or 1642-54-2 Dyphylline 479-18-5 Eplerenone 107724-20-9 Etomidate 33125-97-2 Fenoldopam 67227-57-0 or 67227-56-9 Leflunomide 75706-12-6 Levosimendan 141505-33-1 Methimazole 60-56-0 Moxifloxacin 151096-09-2 or 186826-86-8 or 192927- 63-2 or 354812-41-2 Phenformin 114-86-3 or 834-28-6 Prilocaine 721-50-6 or 14289-31-7 or 14289-32-8 Quinacrine 83-89-6 or 69-05-6 or 6151-30-0 Sulodexide 57821-29-1 Terbinafine 91161-71-6 Trimetazidine 5011-34-7 or 13171-25-0 Zonisamide 68291-97-4

Specific examples of prodrugs of Baclofen are given in Hanafi et al., 2011 (41), particularly Baclofen esters and Baclofen ester carbamates which are of particular interest for CNS targeting. Hence such prodrugs are particularly suitable for compositions of this invention. Arbaclofen Placarbil as mentioned before is also a well-known prodrug and may thus be used instead of Baclofen in compositions of the invention. Other prodrugs of Baclofen can be found in the following patent applications: WO2010/102071, US2009/197958, WO2009/096985, WO2009/061934, WO2008/086492, US2009/216037, WO2005/066122, US2011/021571, WO2003/077902, and WO2010/120370.

Useful prodrugs for acamprosate such as pantoic acid ester neopentyl sulfonyl esters, neopentyl sulfonyl ester prodrugs or masked carboxylate neopentyl sulfonyl ester prodrugs of acamprosate, are notably listed in WO2009/033069, WO2009/033061, WO2009/033054 WO2009/052191, WO2009/033079, US2009/0099253, US2009/0069419, US2009/0082464, US2009/0082440, and US2009/0076147.

In a preferred embodiment, the invention relates to a composition comprising:

-   -   at least one first compound selected from Torasemide,         Trimetazidine, Mexiletine, Ifenprodil, Bromocriptine and         Moxifloxacin, or salt(s), prodrug(s), derivative(s) of any         chemical purity, or sustained-release formulation(s) thereof, in         combination with     -   at least one second compound, distinct from said first compound,         selected from Sulfisoxazole, Methimazole, Prilocaine,         Dyphylline, Quinacrine, Carbenoxolone, Acamprosate, Aminocaproic         acid, Baclofen, Cabergoline, Diethylcarbamazine, Cinacalcet,         Cinnarizine, Eplerenone, Fenoldopam, Leflunomide, Levosimendan,         Sulodexide, Terbinafine, Zonisamide, Etomidate, Phenformin,         Trimetazidine, Mexiletine, Bromocriptine, Ifenprodil, Torasemide         and Moxifloxacin, or salt(s), prodrug(s), derivative(s) of any         chemical purity, or sustained-release formulation(s) thereof,         for use in the treatment of a neurological disorder in a subject         in need thereof.

In a particular embodiment, the invention relates to the use of these drugs or compositions for treating AD or a related disorder in a subject in need thereof.

In a particular embodiment, the invention relates to the use of these drugs or compositions for treating MS, PD, ALS, HD, neuropathies (for instance, neuropathic pain or alcoholic neuropathy), alcoholism or alcohol withdrawal, or spinal cord injury in a subject in need thereof.

As disclosed in the examples, composition therapies using one or more of the above-listed drugs lead to an efficient correction of Alzheimer's disease and other neurological diseases. As illustrated in the Examples section, compositions comprising at least Torasemide, Trimetazidine, Mexiletine, Ifenprodil, Bromocriptine, and Moxifloxacin provide substantial therapeutic and biological effects to prevent the toxic effects of amyloid β (Aβ) protein or peptide on human cells. Moreover, in vivo, these compositions lead to an improvement of cognitive symptoms as well as to an inhibition of molecular pathways triggered by Aβ intoxication, within which glutamate excitotoxicity. Hence, they represent novel and potent methods for treating such diseases.

The Examples section further shows that the above-mentioned compositions are also efficient at i) synergistically protecting in vitro neuronal cells from glutamate toxicity, and ii) conferring clinical benefit in in vivo models for diseases related to glutamate excitotoxicity.

More preferably, drug compositions of the invention may comprise 1, 2, 3, 4 or 5 distinct drugs, even more preferably 2, 3 or 4 distinct drugs for combinatorial treatment of Alzheimer's disease (AD), AD-related disorders, MS, PD, ALS, HD, neuropathies (for instance, neuropathic pain or alcoholic neuropathy), alcoholism or alcohol withdrawal, or spinal cord injury in a subject in need thereof. In a preferred embodiment, the drugs of the invention are used in combination(s) for combined, separate or sequential administration, in order to provide the most effective effect.

In a particular embodiment, the composition comprises (i) Torasemide and (ii) a compound selected from Bromocriptine, Baclofen, Sulfisoxazole, Eplerenone or Terbinafine, or a salt, prodrug, derivative, or sustained-release formulation of said compounds (i) and (ii).

In another particular embodiment, the composition comprises (i) Trimetazidine and (ii) a compound selected from Baclofen, Cinnarizine, Zonisamide, or Moxifloxacin, or a salt, prodrug, derivative, or sustained-release formulation of said compounds (i) and (ii).

According to a further particular embodiment, the composition comprises (i) Moxifloxacin and (ii) a compound selected from Baclofen, Cinacalcet, Zonisamide, Sulfisoxazole, or Trimetazidine, or a salt, prodrug, derivative, or sustained-release formulation of said compounds (i) and (ii).

In another further particular embodiment, the composition comprises (i) Mexiletine and (ii) a compound selected from Baclofen, Cinacalcet, Ifenprodil, or Levosimendan, or a salt, prodrug, derivative, or sustained-release formulation of said compounds (i) and (ii).

A particular embodiment also relates to a composition comprising (i) Ifenprodil and (ii) a compound selected from Acamprosate, Levosimendan, or Mexiletine, or a salt, prodrug, derivative, or sustained-release formulation of said compounds (i) and (ii).

Preferred compositions of the invention, for use in the treatment of a neurological disorder such as Alzheimer's disease (AD), AD-related disorders, MS, PD, ALS, HD, neuropathies (for instance, neuropathic pain or alcoholic neuropathy), alcoholism or alcohol withdrawal, or spinal cord injury, comprise one of the following drug combinations, for combined, separate or sequential administration:

-   -   Baclofen and Torasemide,     -   Eplerenone and Torasemide,     -   Acamprosate and Ifenprodil,     -   Baclofen and Mexiletine,     -   Baclofen and Trimetazidine,     -   Bromocriptine and Sulfisoxazole,     -   Cinacalcet and Mexiletine,     -   Cinnarizine and Trimetazidine,     -   Sulfisoxazole and Torasemide,     -   Trimetazidine and Zonisamide,     -   Levosimendan and Mexiletine,     -   Levosimendan and Ifenprodil,     -   Levosimendan and Trimetazidine,     -   Levosimendan and Moxifloxacin,     -   Terbinafine and Torasemide,     -   Moxifloxacin and Trimetazidine,     -   Moxifloxacin and Baclofen,     -   Moxifloxacin and Cinacalcet,     -   Moxifloxacin and Zonisamide,     -   Moxifloxacin and Sulfisoxazole, or     -   Mexiletine and Ifenprodil.

Examples of preferred compositions according to the invention comprising a combination of at least three compounds, for combined, separate or sequential administration, are provided below:

-   -   Baclofen and Trimetazidine and Torasemide,     -   Baclofen and Cinacalcet and Torasemide,     -   Baclofen and Acamprosate and Torasemide,     -   Levosimendan and Baclofen and Trimetazidine,     -   Levosimendan and Aminocaproic acid and Trimetazidine,     -   Levosimendan and Terbinafine and Trimetazidine, or     -   Levosimendan and Sulfisoxazole and Trimetazidine.

Examples of preferred compositions according to the invention comprising a combination of at least four compounds, for combined, separate or sequential administration, are provided below:

-   -   Sulfisoxazole and Trimetazidine and Torasemide and Zonisamide,     -   Sulfisoxazole and Mexiletine and Torasemide and Cinacalcet,     -   Baclofen and Acamprosate and Torasemide and Diethylcarbamazine,         or     -   Baclofen and Acamprosate and Torasemide and Ifenprodil.

As disclosed in the Examples section, the above combination therapies of the invention induce a strong neuroprotective effect against Aβ toxicity and give positive results in behavioral performances and biochemical assays in vivo. The results show that compositions of the invention i) efficiently correct molecular pathways triggered, in vivo, by Aβ aggregates and ii) lead to an improvement of neurophysiological impairments, observed in diseased animals as neuron survival or synapse integrity.

Moreover, the results presented show also that the above combination therapies have an important synergistic neuroprotective effect against glutamate excitotoxicity (FIGS. 24 and 25; Table 8), a pathway which is implicated in various neurological diseases such as AD, MS, PD, ALS, HD, neuropathies (for instance, neuropathic pain or alcoholic neuropathy), alcoholism or alcohol withdrawal, or spinal cord injury. These therapies give positive results in in vivo or in vitro models for these diseases.

In addition, in vivo results also show that compositions of the invention efficiently restore blood-brain barrier integrity, which is known to be impaired in several neurological diseases.

An object of this invention thus also resides in a composition as defined above for treating a neurological disorder such as Alzheimer's disease (AD), AD-related disorders, MS, PD, ALS, HD, neuropathies (for instance, alcoholic neuropathy or neuropathic pain), alcoholism or alcohol withdrawal, or spinal cord injury.

A further object of this invention resides in the use of a composition as defined above for the manufacture of a medicament for treating a neurological disorder such as Alzheimer's disease (AD), AD-related disorders, MS, PD, ALS, HD, neuropathies (for instance, neuropathic pain or alcoholic neuropathy), alcoholism or alcohol withdrawal, or spinal cord injury.

The invention further provides a method for treating a neurological disorder such as Alzheimer's disease (AD), AD-related disorders, MS, PD, ALS, HD, neuropathies (for instance, neuropathic pain or alcoholic neuropathy), alcoholism or alcohol withdrawal, or spinal cord injury, comprising administering to a subject in need thereof an effective amount of a composition as disclosed above.

As indicated previously, the compounds in a combinatorial treatment or composition of the present invention may be formulated together or separately, and administered together, separately or sequentially and/or repeatedly.

In this regard, a particular object of this invention is a method for treating AD, an AD-related disorder, MS, PD, ALS, HD, neuropathies (for instance, neuropathic pain or alcoholic neuropathy), alcoholism or alcohol withdrawal, or spinal cord injury in a subject, comprising administering simultaneously, separately or sequentially to a subject in need of such a treatment an effective amount of a composition as disclosed above.

In a preferred embodiment, the invention relates to a method of treating Alzheimer's disease (AD), an AD-related disorder, MS, PD, ALS, HD, neuropathies (for instance, neuropathic pain or alcoholic neuropathy), alcoholism or alcohol withdrawal, or spinal cord injury in a subject in need thereof, comprising administering to the subject an effective amount of Torasemide, Trimetazidine, Mexiletine, Ifenprodil, Bromocriptine or Moxifloxacin, or salt(s), prodrug(s), derivative(s) or sustained-release formulation(s) thereof, preferably in a combination as disclosed above.

In another embodiment, this invention relates to a method of treating Alzheimer's disease (AD), an AD-related disorder, MS, PD, ALS, HD, neuropathies (for instance, neuropathic pain or alcoholic neuropathy), alcoholism or alcohol withdrawal, or spinal cord injury in a subject in need thereof, comprising simultaneously, separately or sequentially administering to the subject at least one first compound selected from the group consisting of Torasemide, Trimetazidine, Mexiletine, Ifenprodil, Bromocriptine and Moxifloxacin, or salts, prodrugs, derivatives, or any formulation thereof, in combination with at least one second compound distinct from said first compound, selected from Sulfisoxazole, Methimazole, Prilocaine, Dyphylline, Quinacrine, Carbenoxolone, Acamprosate, Aminocaproic acid, Baclofen, Cabergoline, Diethylcarbamazine, Cinacalcet, Cinnarizine, Eplerenone, Fenoldopam, Leflunomide, Levosimendan, Sulodexide, Terbinafine, Zonisamide, Etomidate, Phenformin, Trimetazidine, Mexiletine, Bromocriptine, Ifenprodil, Torasemide, and Moxifloxacin, or salts, prodrugs, derivatives, or any formulation thereof.

In a further embodiment, the invention relates to a method of treating Alzheimer's disease (AD), an AD-related disorder, MS, PD, ALS, HD, neuropathies (for instance, neuropathic pain or alcoholic neuropathy), alcoholism or alcohol withdrawal, or spinal cord injury, comprising administering to a subject in need thereof at least one first compound selected from the group consisting of Torasemide, Trimetazidine, Mexiletine, Ifenprodil, Bromocriptine and Moxifloxacin, or salts, prodrugs, derivatives, or any formulation thereof, in combination with at least one second compound distinct from said first compound, selected from Sulfisoxazole, Methimazole, Prilocaine, Dyphylline, Quinacrine, Carbenoxolone, Acamprosate, Aminocaproic acid, Baclofen, Cabergoline, Diethylcarbamazine, Cinacalcet, Cinnarizine, Eplerenone, Fenoldopam, Leflunomide, Levosimendan, Sulodexide, Terbinafine, Zonisamide, Etomidate, Phenformin, Trimetazidine, Mexiletine, Bromocriptine, Ifenprodil, Torasemide, and Moxifloxacin, or salts, prodrugs, derivatives, or any formulation thereof.

As disclosed in the examples, besides being efficient at protecting neurons from glutamate toxicity, Baclofen-Torasemide therapy is also particularly efficient at promoting neuronal cell growth, even in the absence of any exposure to a toxic agent or condition. Moreover, in vivo, this combination therapy leads to an improvement of loss of transduction of nervous signals subsequent to nerve injury. Hence, the Baclofen-Torasemide combination represents a novel and potent therapy for treating neuropathies, nerve injuries, and spinal cord injuries as defined above.

In this regard, in a particular embodiment, the invention relates to a method for treating neuropathies, e.g., peripheral nerve injuries or spinal cord injuries, comprising administering to a subject in need thereof a composition comprising Baclofen and Torasemide, or salts, prodrugs, derivatives, or any formulation thereof.

In another particular embodiment, the invention relates to a method for treating neuropathies, e.g., inherited neuropathies such as CMT diseases, comprising administering to a subject in need thereof a composition comprising Baclofen and Torasemide, or salts, prodrugs, derivatives, or any formulation thereof.

In a more particular embodiment, the invention relates to a method for treating CMT1 or CMT2 disease, comprising administering to a subject in need thereof a composition comprising Baclofen and Torasemide, or salts, prodrugs, derivatives, or any formulation thereof.

A particular object of this invention is also a method for treating neuropathies, e.g., peripheral nerve injuries or spinal cord injuries, comprising administering simultaneously, separately or sequentially and/or repeatedly to a subject in need of such a treatment an effective amount of Baclofen and Torasemide as disclosed above.

Although very effective in vitro and in vivo, depending on the subject or specific condition, the methods and compositions of the invention may be used in further conjunction with additional drugs or treatments beneficial to treating the neurological condition in the subjects. In this regard, in a particular embodiment, the drug(s) or composition(s) according to the present invention may be further combined with Ginkgo biloba extracts. Suitable extracts include, without limitation, Ginkgo biloba extracts, improved Ginkgo biloba extracts (for example, enriched in active ingredients or lessened in contaminants) or any drug containing Ginkgo biloba extracts.

Ginkgo biloba extracts may be used in a composition comprising at least Torasemide, Trimetazidine, Mexiletine, Bromocriptine, Ifenprodil and Moxifloxacin.

In preferred embodiments, Ginkgo biloba extracts are used in combination with anyone of the following drug combinations:

-   -   Acamprosate and Ifenprodil,     -   Baclofen and Mexiletine,     -   Baclofen and Torasemide,     -   Baclofen and Trimetazidine,     -   Bromocriptine and Sulfisoxazole,     -   Cinacalcet and Mexiletine,     -   Cinnarizine and Trimetazidine,     -   Eplerenone and Torasemide,     -   Sulfisoxazole and Torasemide,     -   Trimetazidine and Zonisamide,     -   Levosimendan and Mexiletine,     -   Levosimendan and Ifenprodil,     -   Levosimendan and Trimetazidine,     -   Levosimendan and Moxifloxacin,     -   Terbinafine and Torasemide,     -   Moxifloxacin and Baclofen,     -   Moxifloxacin and Cinacalcet,     -   Moxifloxacin and Zonisamide,     -   Moxifloxacin and Sulfisoxazole,     -   Mexiletine and Ifenprodil,     -   Baclofen and Trimetazidine and Torasemide,     -   Baclofen and Cinacalcet and Torasemide,     -   Baclofen and Acamprosate and Torasemide,     -   Sulfisoxazole and Trimetazidine and Torasemide and Zonisamide,     -   Sulfisoxazole and Mexiletine and Torasemide and Cinacalcet,     -   Baclofen and Acamprosate and Torasemide and Diethylcarbamazine,     -   Baclofen and Acamprosate and Torasemide and Ifenprodil,     -   Levosimendan and Baclofen and Trimetazidine,     -   Levosimendan and Aminocaproic acid and Trimetazidine,     -   Levosimendan and Terbinafine and Trimetazidine, or     -   Levosimendan and Sulfisoxazole and Trimetazidine.

Other therapies used in conjunction with drug(s) or drug combination(s) according to the present invention may comprise one or more drug(s) that ameliorate symptoms of Alzheimer's disease, an AD-related disorder, MS, PD, ALS, HD, neuropathies (for instance, neuropathic pain or alcoholic neuropathy), alcoholism or alcohol withdrawal, or spinal cord injury, or drug(s) that could be used for palliative treatment of these disorders.

For instance, combinations of the invention can be used in conjunction with Donepezil (CAS: 120014-06-4), Gabapentine (CAS: 478296-72-9; 60142-96-3), Galantamine (CAS: 357-70-0), Rivastigmine (CAS: 123441-03-2) or Memantine (CAS: 19982-08-2).

A further object of this invention relates to the use of a compound or combination of compounds as disclosed above for the manufacture of a medicament for the treatment of the above-listed disorders, by combined, separate or sequential administration to a subject in need thereof.

A further object of this invention is a method of preparing a pharmaceutical composition, the method comprising mixing the above compounds in an appropriate excipient or carrier.

The duration of the therapy depends on the stage of the disease or disorder being treated, the combination used, the age and condition of the patient, and how the patient responds to the treatment. The dosage, frequency and mode of administration of each component of the combination can be controlled independently. For example, one drug may be administered orally while the second drug may be administered intramuscularly. Combination therapy may be given in on-and-off cycles that include rest periods so that the patient's body has a chance to recover from any as yet unforeseen side effects. The drugs may also be formulated together such that one administration delivers all drugs.

The administration of each drug of the combination may be by any suitable means that results in a concentration of the drug that, combined with the other component, is able to ameliorate the patient's condition or efficiently treat the disease or disorder.

While it is possible for the active ingredients of the combination to be administered as the pure chemical it is preferable to present them as a pharmaceutical composition, also referred to in this context as a pharmaceutical formulation. Possible compositions include those suitable for oral, rectal, topical (including transdermal, buccal and sublingual), or parenteral (including subcutaneous, intramuscular, intravenous and intradermal) administration.

More commonly these pharmaceutical formulations are prescribed to the patient in “patient packs” containing a number of dosing units or other means for administration of metered unit doses for use during a distinct treatment period in a single package, usually a blister pack. Patient packs have an advantage over traditional prescriptions, where a pharmacist divides a patient's supply of a pharmaceutical from a bulk supply, in that the patient always has access to the package insert contained in the patient pack, normally missing in traditional prescriptions. The inclusion of a package insert has been shown to improve patient compliance with the physician's instructions. Thus, the invention further includes a pharmaceutical formulation, as herein described, in combination with packaging material suitable for said formulations. In such a patient pack the intended use of a formulation for the combination treatment can be inferred by instructions, facilities, provisions, adaptations and/or other means to help use the formulation most suitably for the treatment. Such measures make a patient pack specifically suitable for and adapted for use for treatment with the combination of the present invention.

The drug may be contained, in any appropriate amount, in any suitable carrier substance (e.g., excipient, vehicle, support), which may represent 1-99% by weight of the total weight of the composition. The composition may be provided in a dosage form that is suitable for the oral, parenteral (e.g., intravenous, intramuscular), rectal, cutaneous, nasal, vaginal, inhalant, skin (patch), or ocular administration route. Thus, the composition may be in the form of, e.g., tablets, capsules, pills, powders, granulates, suspensions, emulsions, solutions, gels including hydrogels, pastes, ointments, creams, plasters, drenches, osmotic delivery devices, suppositories, enemas, injectables, implants, sprays, or aerosols.

The pharmaceutical compositions may be formulated according to conventional pharmaceutical practice (see, e.g., Remington: The Science and Practice of Pharmacy (20th ed.), ed. A.R. Gennaro, Lippincott Williams & Wilkins, 2000 and Encyclopedia of Pharmaceutical Technology, eds. J. Swarbrick and J. C. Boylan, 1988-1999, Marcel Dekker, New York).

Pharmaceutical compositions according to the invention may be formulated to release the active drug substantially immediately upon administration or at any predetermined time or time period after administration.

The controlled release formulations include (i) formulations that create a substantially constant concentration of the drug within the body over an extended period of time; (ii) formulations that after a predetermined lag time create a substantially constant concentration of the drug within the body over an extended period of time; (iii) formulations that sustain drug action during a predetermined time period by maintaining a relatively constant, effective drug level in the body with concomitant minimization of undesirable side effects associated with fluctuations in the plasma level of the active drug substance; (iv) formulations that localize drug action by, e.g., spatial placement of a controlled-release composition adjacent to or in the diseased tissue or organ; and (v) formulations that target drug action by using carriers or chemical derivatives to deliver the drug to a particular target cell type.

Administration of drugs in the form of a controlled-release formulation is especially preferred in cases in which the drug, either alone or in combination, has: (i) a narrow therapeutic index (i.e., the difference between the plasma concentration leading to harmful side effects or toxic reactions and the plasma concentration leading to a therapeutic effect is small; in general, the therapeutic index, TI, is defined as the ratio of median lethal dose (LD₅₀) to median effective dose (ED₅₀)); (ii) a narrow absorption window in the gastrointestinal tract; or (iii) a very short biological half-life so that frequent dosing during a day is required in order to sustain the plasma level at a therapeutic level.

Any of a number of strategies can be pursued in order to obtain controlled release in which the rate of release outweighs the rate of metabolism of the drug in question. Controlled release may be obtained by appropriate selection of various formulation parameters and ingredients, including, e.g., various types of controlled-release compositions and coatings. Thus, the drug is formulated with appropriate excipients into a pharmaceutical composition that, upon administration, releases the drug in a controlled manner (single or multiple unit tablet or capsule compositions, oil solutions, suspensions, emulsions, microcapsules, microspheres, nanoparticles, patches, and liposomes).

Solid Dosage Forms for Oral Use

Formulations for oral use include tablets containing the active ingredient(s) in a mixture with non-toxic pharmaceutically acceptable excipients. These excipients may be, for example, inert diluents or fillers (e.g., sucrose, microcrystalline cellulose, starches including potato starch, calcium carbonate, sodium chloride, calcium phosphate, calcium sulfate, or sodium phosphate); granulating and disintegrating agents (e.g., cellulose derivatives including microcrystalline cellulose, starches including potato starch, croscarmellose sodium, alginates, or alginic acid); binding agents (e.g., acacia, alginic acid, sodium alginate, gelatin, starch, pregelatinized starch, microcrystalline cellulose, carboxymethylcellulose sodium, methylcellulose, hydroxypropyl methylcellulose, ethylcellulose, polyvinylpyrrolidone, or polyethylene glycol); and lubricating agents, glidants, and antiadhesives (e.g., stearic acid, silicas, or talc). Other pharmaceutically acceptable excipients can be colorants, flavoring agents, plasticizers, humectants, buffering agents, and the like.

The tablets may be uncoated or they may be coated by known techniques, optionally to delay disintegration and absorption in the gastrointestinal tract and thereby providing a sustained action over a longer period. The coating may be adapted to release the active drug substance in a predetermined pattern (e.g., in order to achieve a controlled-release formulation) or it may be adapted not to release the active drug substance until after passage of the stomach (enteric coating). The coating may be a sugar coating, a film coating (e.g., based on hydroxypropyl methylcellulose, methylcellulose, methyl hydroxyethylcellulose, hydroxypropylcellulose, carboxymethylcellulose, acrylate copolymers, polyethylene glycols and/or polyvinylpyrrolidone), or an enteric coating (e.g., based on methacrylic acid copolymer, cellulose acetate phthalate, hydroxypropyl methylcellulose phthalate, hydroxypropyl methylcellulose acetate succinate, polyvinyl acetate phthalate, shellac, and/or ethylcellulose). A time delay material such as glyceryl monostearate or glyceryl distearate may be employed.

The solid tablet compositions may include a coating adapted to protect the composition from unwanted chemical changes, (e.g., chemical degradation prior to the release of the active drug substance). The coating may be applied on the solid dosage form in a similar manner to that described in the Encyclopedia of Pharmaceutical Technology.

Several drugs may be mixed together in the tablet, or may be partitioned. For example, the first drug is contained on the inside of the tablet, and the second drug is on the outside, such that a substantial portion of the second drug is released prior to the release of the first drug.

Formulations for oral use may also be presented as chewable tablets, as hard gelatin capsules wherein the active ingredient is mixed with an inert solid diluent (e.g., potato starch, microcrystalline cellulose, calcium carbonate, calcium phosphate or kaolin), or as soft gelatin capsules wherein the active ingredient is mixed with water or an oil medium, for example, liquid paraffin or olive oil. Powders and granulates may be prepared using the ingredients mentioned above under tablets and capsules in a conventional manner.

Controlled-release compositions for oral use may, e.g., be constructed to release the active drug by controlling the dissolution and/or the diffusion of the active drug sub stance.

Dissolution or diffusion controlled release can be achieved by appropriate coating of a tablet, capsule, pellet, or granular formulation of drugs, or by incorporating the drug into an appropriate matrix. A controlled-release coating may include one or more of the coating substances mentioned above and/or, e.g., shellac, beeswax, glycowax, castor wax, carnauba wax, stearyl alcohol, glyceryl monostearate, glyceryl distearate, glycerol palmitostearate, ethylcellulose, acrylic resins, dl-polylactic acid, cellulose acetate butyrate, polyvinyl chloride, polyvinyl acetate, vinyl pyrrolidone, polyethylene, polymethacrylate, methylmethacrylate, 2-hydroxymethacrylate, methacrylate hydrogels, 1,3 butylene glycol, ethylene glycol methacrylate, and/or polyethylene glycols. In a controlled-release matrix formulation, the matrix material may also include, e.g., hydrated methylcellulose, carnauba wax, stearyl alcohol, carbopol 934, silicone, glyceryl tristearate, methyl acrylate-methyl methacrylate, polyvinyl chloride, polyethylene, and/or halogenated fluorocarbon.

A controlled-release composition containing one or more of the drugs of the claimed combinations may also be in the form of a buoyant tablet or capsule (i.e., a tablet or capsule that, upon oral administration, floats on top of the gastric content for a certain period of time). A buoyant tablet formulation of the drug(s) can be prepared by granulating a mixture of the drug(s) with excipients and 20-75% w/w of hydrocolloids, such as hydroxyethylcellulose, hydroxypropylcellulose, or hydroxypropylmethylcellulose. The obtained granules can then be compressed into tablets. On contact with the gastric juice, the tablet forms a substantially water-impermeable gel barrier around its surface. This gel barrier takes part in maintaining a density of less than one, thereby allowing the tablet to remain buoyant in the gastric juice.

Liquids for Oral Administration

Powders, dispersible powders, or granules suitable for preparation of an aqueous suspension by addition of water are convenient dosage forms for oral administration. Formulation as a suspension provides the active ingredient in a mixture with a dispersing or wetting agent, suspending agent, and one or more preservatives. Suitable suspending agents are, for example, sodium carboxymethylcellulose, methylcellulose, sodium alginate, and the like.

Parenteral Compositions

The pharmaceutical composition may also be administered parenterally by injection, infusion or implantation (intravenous, intramuscular, subcutaneous, or the like) in dosage forms, formulations, or via suitable delivery devices or implants containing conventional, non-toxic pharmaceutically acceptable carriers and adjuvants. The formulation and preparation of such compositions are well-known to those skilled in the art of pharmaceutical formulation.

Compositions for parenteral use may be provided in unit dosage forms (e.g., in single-dose ampoules), or in vials containing several doses and in which a suitable preservative may be added (see below). The composition may be in the form of a solution, a suspension, an emulsion, an infusion device, or a delivery device for implantation or it may be presented as a dry powder to be reconstituted with water or another suitable vehicle before use. Apart from the active drug(s), the composition may include suitable parenterally acceptable carriers and/or excipients. The active drug(s) may be incorporated into microspheres, microcapsules, nanoparticles, liposomes, or the like for controlled release. The composition may include suspending, solubilizing, stabilizing, pH-adjusting, and/or dispersing agents.

The pharmaceutical compositions according to the invention may be in a form suitable for sterile injection. To prepare such a composition, the suitable active drug(s) are dissolved or suspended in a parenterally acceptable liquid vehicle. Among acceptable vehicles and solvents that may be employed are water, water adjusted to a suitable pH by addition of an appropriate amount of hydrochloric acid, sodium hydroxide or a suitable buffer, 1,3-butanediol, Ringer's solution, and isotonic sodium chloride solution. The aqueous formulation may also contain one or more preservatives (e.g., methyl, ethyl or n-propyl p-hydroxybenzoate). In cases where one of the drugs is only sparingly or slightly soluble in water, a dissolution-enhancing or solubilizing agent can be added, or the solvent may include 10-60% w/w of propylene glycol or the like.

Controlled-release parenteral compositions may be in form of aqueous suspensions, microspheres, microcapsules, magnetic microspheres, oil solutions, oil suspensions, or emulsions. Alternatively, the active drug(s) may be incorporated in biocompatible carriers, liposomes, nanoparticles, implants, or infusion devices. Materials for use in the preparation of microspheres and/or microcapsules are, e.g., biodegradable/bioerodible polymers such as polygalactin, poly-(isobutyl cyanoacrylate), and poly(2-hydroxyethyl-L-glutamine). Biocompatible carriers that may be used when formulating a controlled-release parenteral formulation are carbohydrates (e.g., dextrans), proteins (e.g., albumin), lipoproteins, or antibodies. Materials for use in implants can be non-biodegradable (e.g., polydimethyl siloxane) or biodegradable (e.g., poly(caprolactone), poly(glycolic acid) or poly(ortho esters)).

Alternative Routes

Although less preferred and less convenient, other administration routes, and therefore other formulations, may be contemplated. In this regard, for rectal application, suitable dosage forms for a composition include suppositories (emulsion or suspension type) and rectal gelatin capsules (solutions or suspensions). In a typical suppository formulation, the active drug(s) are combined with an appropriate pharmaceutically acceptable suppository base such as cocoa butter, esterified fatty acids, glycerinated gelatin, and various water-soluble or dispersible bases like polyethylene glycols. Various additives, enhancers, or surfactants may be incorporated.

The pharmaceutical compositions may also be administered topically on the skin for percutaneous absorption in dosage forms or formulations containing conventionally non-toxic pharmaceutically acceptable carriers and excipients, including microspheres and liposomes. The formulations include creams, ointments, lotions, liniments, gels, hydrogels, solutions, suspensions, sticks, sprays, pastes, plasters, and other kinds of transdermal drug delivery systems. The pharmaceutically acceptable carriers or excipients may include emulsifying agents, antioxidants, buffering agents, preservatives, humectants, penetration enhancers, chelating agents, gel-forming agents, ointment bases, perfumes, and skin protective agents.

The preservatives, humectants, penetration enhancers may be parabens, such as methyl or propyl p-hydroxybenzoate, and benzalkonium chloride, glycerin, propylene glycol, urea, etc.

The pharmaceutical compositions described above for topical administration on the skin may also be used in connection with topical administration onto or close to the part of the body that is to be treated. The compositions may be adapted for direct application or for application by means of special drug delivery devices such as dressings or, alternatively, plasters, pads, sponges, strips, or other forms of suitable flexible material.

Dosages and Duration of the Treatment

It will be appreciated that the drugs of the combination may be administered concomitantly, either in the same or different pharmaceutical formulations or sequentially. If there is sequential administration, the delay in administering the second (or additional) active ingredient should not be such as to lose the benefit of the efficacious effect of the combination of the active ingredients. A minimum requirement for a combination according to this description is that the combination should be intended for combined use with the benefit of the efficacious effect of the combination of the active ingredients. The intended use of a combination can be inferred by facilities, provisions, adaptations and/or other means to help use the combination according to the invention.

Although the active drugs of the present invention may be administered in divided doses, for example two or three times daily, a single daily dose of each drug in the combination is preferred, with a single daily dose of all drugs in a single pharmaceutical composition (unit dosage form) being most preferred.

The term “unit dosage form” refers to physically discrete units (such as capsules, tablets, or loaded syringe cylinders) suitable as unitary dosages for human subjects, each unit containing a predetermined quantity of active material or materials calculated to produce the desired therapeutic effect, in association with the required pharmaceutical carrier.

Administration is generally repeated. It can be one to several times daily for several days to several years, and may even be for the life of the patient. Chronic or at least periodically repeated long-term administration is indicated in most cases.

Additionally, pharmacogenomic (the effect of genotype on the pharmacokinetic, pharmacodynamic or efficacy profile of a therapeutic) information about a particular patient may affect the dosage used.

Except when responding to especially impairing cases when higher dosages may be required, the preferred dosage of each drug in the combination usually lies within the range of doses not above those usually prescribed for long-term maintenance treatment or proven to be safe in phase 3 clinical studies.

One remarkable advantage of the invention is that each compound may be used at low doses in a combination therapy, while producing, in combination, a substantial clinical benefit to the patient. The combination therapy may indeed be effective at doses where the compounds individually have no substantial effect. Accordingly, a particular advantage of the invention lies in the ability to use sub-optimal doses of each compound, i.e., doses which are lower than the therapeutic doses usually prescribed, preferably ½ of the therapeutic doses, more preferably ⅓, ¼, ⅕, or even more preferably 1/10 of the therapeutic doses. In particular examples, doses as low as 1/20, 1/30, 1/50, 1/100, or even lower of the therapeutic doses are used.

At such sub-optimal dosages, the compounds alone would be substantially inactive, while the combination(s) according to the invention are fully effective.

A preferred dosage corresponds to amounts from 1% up to 50% of those usually prescribed for long-term maintenance treatment.

The most preferred dosage may correspond to amounts from 1% up to 10% of those usually prescribed for long-term maintenance treatment.

Specific examples of dosages of drugs for use in the invention are provided below:

-   -   Bromocriptine orally from about 0.01 to 10 mg per day,         preferably less than 5 mg per day, more preferably less than 2.5         mg per day, even more preferably less than 1 mg per day, such         dosages being particularly suitable for oral administration,     -   Ifenprodil orally from about 0.4 to 6 mg per day, preferably         less than 3 mg per day, more preferably less than 1.5 mg per         day, even more preferably less than 0.75 mg per day, such         dosages being particularly suitable for oral administration,     -   Mexiletine orally from about 6 to 120 mg per day, preferably         less than 60 mg per day, more preferably less than 30 mg per         day, even more preferably less than 15 mg per day, such dosages         being particularly suitable for oral administration,     -   Moxifloxacin orally from about 4 to 40 mg per day, preferably         less than 20 mg per day, more preferably less than 10 mg per         day, even more preferably less than 5 mg per day, such dosages         being particularly suitable for oral administration,     -   Torasemide orally from about 0.05 to 4 mg per day, preferably         less than 2 mg per day, more preferably less than 1 mg per day,         even more preferably less than 0.5 mg per day, such dosages         being particularly suitable for oral administration,     -   Trimetazidine orally from about 0.4 to 6 mg per day, preferably         less than 3 mg per day, more preferably less than 1.5 mg per         day, even more preferably less than 0.75 mg per day, such         dosages being particularly suitable for oral administration,     -   Acamprosate orally from about 1 to 400 mg per day,     -   Aminocaproic Acid orally from about 0.1 g to 2.4 g per day,     -   Baclofen between 0.01 and 150 mg per day, preferably less than         100 mg per day, more preferably less than 50 mg per day, most         preferably between 5 and 40 mg per day, even more preferably         less than 35 mg per day, typically 15 mg per day, 12 mg per day,         24 mg per day, or 30 mg per day, such dosages being particularly         suitable for oral administration,     -   Diethylcarbamazine orally from about 0.6 to 600 mg per day,     -   Cinacalcet orally from about 0.3 to 36 mg per day,     -   Cinnarizine orally from about 0.6 to 23 mg per day,     -   Eplerenone orally from about 0.25 to 10 mg per day,     -   Leflunomide orally from about 0.1 to 10 mg per day,     -   Levosimendan orally from about 0.04 to 0.8 mg per day,     -   Sulfisoxazole orally from about 20 to 800 mg per day,     -   Sulodexide orally from about 0.05 to 40 mg per day,     -   Terbinafine orally from about 2.5 to 25 mg per day, and     -   Zonisamide orally from about 0.5 to 50 mg per day.

It will be understood that the amount of the drug actually administered will be determined by a physician, in light of the relevant circumstances including the condition or conditions to be treated, the exact composition to be administered, the age, weight, and response of the individual patient, the severity of the patient's symptoms, and the chosen route of administration. Therefore, the above dosage ranges are intended to provide general guidance and support for the teachings herein, but are not intended to limit the scope of the invention.

The following examples are given for purposes of illustration and not by way of limitation.

EXAMPLES

The care and husbandry of animals as well as the experimentations are performed according to the guidelines of the Committee for Research and Ethical Issues of the I.A.S.P. (1983).

A) Treatment of Diseases Related to Aβ Toxicity

In this series of experiments, candidate compounds have been tested for their ability to prevent or reduce the toxic effects of human Aβ₁₋₄₂. Aβ₁₋₄₂ is the full-length peptide that constitutes aggregates found in biopsies from human patients afflicted with AD. The drugs are first tested individually, followed by assays of their combinatorial action. The effect is determined on various cell types, to further document the activity of the compounds in in vitro models which illustrate different physiological features of AD. In vivo studies are also performed in a mouse model for AD, confirming this protective effect by evaluating the effect of the compounds on i) the cognitive performance of animals and ii) molecular hallmarks (apoptosis induction, oxidative stress induction, inflammation pathway induction) of AD.

I. The Compounds Prevent Toxicity of Human Aβ₁₋₄₂

I.1. Protection Against the Toxicity of Aβ₁₋₄₂ in Human Brain Microvascular Endothelial Cell Model

Human brain microvascular endothelial cell cultures were used to study the protection afforded by candidate compound(s) on Aβ₁₋₄₂ toxicity.

Human brain microvascular endothelial cerebral cells (HBMEC, ScienCell Ref: 1000, frozen at passage 10) were rapidly thawed in a water bath at +37° C. The supernatant was immediately put in 9 ml Dulbecco's modified Eagle's medium (DMEM; Pan Biotech ref: P04-03600) containing 10% of fetal calf serum (FCS; Gibco ref: 10270-106). The cell suspension was centrifuged at 180×g for 10 min at +4° C. and the pellets were suspended in CSC serum-free medium (Cell Systems, ref: SF-4Z0-500-R, batch 51407-4) with 1.6% of serum-free RocketFuel (Cell Systems, ref: SF-4Z0-500-R, batch 54102), 2% of penicillin 10,000 U/ml and streptomycin 10 mg/ml (PS; Pan Biotech ref: P06-07100, batch 133080808) and were seeded at the density of 20,000 cells per well in 96-well plates (matrigel layer biocoat angiogenesis system, BD Biosciences, ref: 354150, batch A8662) in a final volume of 100 μl. On matrigel support, endothelial cerebral cells spontaneously started the process of capillary network morphogenesis (33).

Three separate cultures were performed per condition, 6 wells per condition.

Candidate Compounds and Human Amyloid-β₁₋₄₂ Treatment

Briefly, Aβ₁₋₄₂ peptide (Bachem, ref: H1368, batch 1010533) was reconstituted in defined culture medium at 20 μM (mother solution) and was slowly shaken at +37° C. for 3 days in the dark for aggregation. The control medium was prepared in the same conditions.

After 3 days, this aggregated human amyloid peptide was used on HBMEC at 2.5 μM diluted in control medium (optimal incubation time). The Aβ₁₋₄₂ peptide was added 2 hours after HBMEC seeding on matrigel for 18 hours of incubation.

One hour after HBMEC seeding on matrigel, test compounds and VEGF-165 were solved in culture medium (+0.1% DMSO) and then pre-incubated with HBMEC for 1 hour before the Aβ₁₋₄₂ application (in a final volume per culture well of 100 μl). 1 hour after test compounds or VEGF incubation (two hours after cell seeding on matrigel), 100 μl of Aβ₁₋₄₂ peptide was added to a final concentration of 2.5 μM diluted in control medium in the presence of test compounds or VEGF (in a 200 μl total volume/well), in order to avoid further drug dilutions.

Organization of Culture Plates

VEGF-165, known to be a pro-angiogenic isoform of VEGF-A, was used for all experiments in this study as a reference compound. VEGF-165 is one of the most abundant VEGF isoforms involved in angiogenesis. VEGF was used as a reference test compound at 10 nM.

The following conditions were assessed:

-   -   Negative Control: medium alone+0.1% DMSO.     -   Intoxication: amyloid-β₁₋₄₂ (2.5 μM) for 18 h     -   Positive control: VEGF-165 (10 nM) (1 reference         compound/culture) 1 hr before the Aβ₁₋₄₂ (2.5 μM) addition for a         18 h incubation time.     -   Test compounds: Test compound 1 hr before the Aβ₁₋₄₂ (2.5 μM)         addition for an 18 h incubation time.         Capillary Network Quantification

Per well, 2 pictures with a 4× lens were taken using InCell Analyzer™ 1000 (GE Healthcare) in light transmission. All images were taken in the same conditions. Analysis of the angiogenesis networks was done using Developer software (GE Healthcare). The total length of the capillary network was assessed.

Data Processing

All values are expressed as mean±s.e. mean of the 3 cultures (n=6 per condition). Statistic analyses were done on the different conditions performing an ANOVA followed by the Dunnett's test when it was allowed (StatView software, version 5.0). The values (as %) inserted on the graphs show the amyloid toxicity evolution. Indeed, the amyloid toxicity was taken as 100% and the test compound effect was calculated as a % of this amyloid toxicity.

Results

Results are shown in FIG. 1. They demonstrate that the drugs tested alone induce a substantial protective effect against the toxicity caused by Aβ peptide 1-42:

-   -   Torasemide, at a low dosage of, e.g., 400 nM, induces a strong         protective effect; and     -   Bromocriptine, at a low dosage of, e.g., 3.2 nM, induces a         strong protective effect.

The results also show that, unexpectedly, upper or lower drug concentrations, in comparison to the above-mentioned drug concentrations, may worsen or have little to no effect on Aβ₁₋₄₂ toxicity in this model.

1.2 Protection Against the Toxicity of Aβ₁₋₄₂ on Primary Cortical Neuron Cells

Test Compound and Human Amyloid-β1-42 Treatment

Rat cortical neurons were cultured as described by Singer et al. (42). Briefly pregnant female rats of 15 days gestation were killed by cervical dislocation (Rats, Wistar) and the fetuses were removed from the uterus. The cortex was removed and placed in ice-cold medium of Leibovitz (L15) containing 2% of penicillin 10,000 U/ml and streptomycin 10 mg/ml and 1% of bovine serum albumin (BSA). Cortices were dissociated by trypsin for 20 min at 37° C. (0.05%). The reaction was stopped by the addition of Dulbecco's modified Eagle's medium (DMEM) containing DNase1 grade II and 10% of fetal calf serum (FCS). Cells were then mechanically dissociated by 3 serial passages through a 10 ml pipette and centrifuged at 515×g for 10 min at +4° C. The supernatant was discarded and the pellet of cells was re-suspended in a defined culture medium consisting of Neurobasal supplemented with B27 (2%), L-glutamine (0.2 mM), 2% of PS solution and 10 ng/ml of BDNF. Viable cells were counted in a Neubauer cytometer using the trypan blue exclusion test. The cells were seeded at a density of 30,000 cells/well in 96-well plates (wells were pre-coated with poly-L-lysine (10 μg/ml)) and were cultured at +37° C. in a humidified air (95%)/CO₂ (5%) atmosphere.

Briefly, Aβ₁₋₄₂ peptide was reconstituted in defined culture medium at 40 μM (mother solution) and was slowly shaken at +37° C. for 3 days in the dark for aggregation. The control medium was prepared in the same conditions.

After 3 days, the solution was used on primary cortical neurons as follows:

After 10 days of neuron culture, the drug was solved in culture medium (+0.1% DMSO) and then pre-incubated with neurons for 1 hour before the Aβ₁₋₄₂ application (in a final volume per culture well of 100 μl). One hour after drug(s) incubation, 100 μl of Aβ₁₋₄₂ peptide was added to a final concentration of 10 μM diluted in the presence of drug(s), in order to avoid further drug(s) dilutions. Cortical neurons were intoxicated for 24 hours. Three separate cultures were performed per condition, 6 wells per condition.

BDNF (50 ng/ml) and Estradiol-β (150 nM) were used as positive control and reference compounds, respectively.

Organization of Cultures Plates

Estradiol-β at 150 nM was used as a positive control.

Estradiol-β was solved in culture medium and pre-incubated for 1 h before the aggregated amyloid-β₁₋₄₂ application.

The following conditions were assessed:

-   -   CONTROL PLAQUE: 12 wells/condition         -   Negative Control: medium alone+0.1% DMSO         -   Intoxication: amyloid-β₁₋₄₂ (10 μM) for 24 h         -   Reference compound: Estradiol (150 nM) 1 h     -   DRUG PLATE: 6 wells/condition         -   Negative Control: medium alone+0.1% DMSO         -   Intoxication: amyloid-β₁₋₄₂ (10 μM) for 24 h         -   Drug: Drug—1 hr followed by amyloid-β₁₋₄₂ (10 μM) for 24 h             Lactate Dehydrogenase (LDH) Activity Assay

24 hours after intoxication, the supernatant was taken off and analyzed with the Cytotoxicity Detection Kit (LDH, Roche Applied Science, ref: 11644793001, batch: 11800300). This colorimetric assay for the quantification of cell toxicity is based on the measurement of lactate dehydrogenase (LDH) activity released from the cytosol of dying cells into the supernatant.

Data Processing

All values are expressed as mean±s.e. mean of the 3 cultures (n=6 per condition). Statistic analyses were done on the different conditions (ANOVA followed by the Dunnett's test when it was allowed, StatView software, version 5.0).

Results

The results obtained for individual selected drugs in the toxicity assays on primary cortical neuron cells are presented in FIGS. 2, 26 and 27. They demonstrate that the drugs tested alone induce a substantial protective effect against the toxicity caused by Aβ peptide 1-42:

-   -   Trimetazidine, at a low dosage of e.g., 40 nM, induces a strong         protective effect;     -   Mexiletine, at a dose as low as 3.2 nM, induces a strong         protective effect;     -   Bromocriptine, at a dose as low as 40 nM, induces a strong         protective effect;     -   Ifenprodil, at a dose as low as 600 nM, induces a strong         protective effect;     -   Moxifloxacin, at a dose as low as 20 nM, induces a strong         protective effect;     -   Torasemide, at a dose of 200 nM, induces a strong protective         effect; and     -   Homotaurine, at a dose of 8 nM, induces a strong protective         effect.

The obtained results also show that, unexpectedly, upper or lower drug concentrations than those indicated above may worsen or have little to no protective effect on Aβ₁₋₄₂ toxicity for neuronal cells.

II. Combined Therapies Prevent Toxicity of Human Aβ₁₋₄₂

II.1 Effect of Combined Therapies on the Toxicity of Human Aβ₁₋₄₂ Peptide on Human HBMEC Cells

The efficacy of drug combinations of the invention is assessed on human cells. The protocol which is used in these assays is the same as described in section I.1 above.

Results

All of the tested drug combinations give a protective effect against the toxicity of human Aβ₁₋₄₂ peptide in the HBMEC model, as shown in Table 3 below and exemplified in FIGS. 3 to 6 and FIGS. 13 and 14. The results clearly show that intoxication by aggregated human amyloid peptide (Aβ₁₋₄₂ 2.5 μM) is significantly prevented by combinations of the invention, whereas, at those concentrations, the drugs alone have no significant effect on intoxication in the experimental conditions described above.

TABLE 3 Protective effect in Aβ₁₋₄₂ intoxicated DRUG COMBINATION HBMEC cells Baclofen and Torasemide + Eplerenone and Torasemide + Bromocriptine and Sulfisoxazole + Sulfisoxazole and Torasemide + Terbinafine and Torasemide + Mexiletine and Cinacalcet + Baclofen and Trimetazidine and Torasemide + Baclofen and Cinacalcet and Torasemide + Baclofen and Acamprosate and Torasemide + Sulfisoxazole and Trimetazidine and Torasemide and + Zonisamide Sulfisoxazole and Mexiletine and Torasemide and + Cinacalcet Baclofen and Acamprosate and Torasemide and + Diethylcarbamazine Baclofen and Acamprosate and Torasemide and + Ifenprodil Levosimendan and Baclofen and Trimetazidine + Levosimendan and Aminocaproic acid and Trimetazidine + Levosimendan and Terbinafine and Trimetazidine + Levosimendan and Sulfisoxazole and Trimetazidine + As exemplified in FIGS. 3 to 6, 13 and 14, the following drug combinations give particularly interesting protective effects against the toxicity of human Aβ₁₋₄₂ peptide in intoxicated HBMEC cells:

-   -   Baclofen and Torasemide,     -   Sulfisoxazole and Torasemide,     -   Torasemide and Eplerenone,     -   Sulfisoxazole and Bromocriptine,     -   Terbinafine and Torasemide, and     -   Cinacalcet and Mexiletine.         II.2 Effect of Combined Therapies on the Toxicity of Human         Aβ₁₋₄₂ Peptide on Primary Cortical Neuron Cells

The efficacy of drug combinations of the invention is assessed on primary cortical neuron cells. The protocol which is used in these assays is the same as described in section 1.2 above.

Results

All of the tested drug combinations give a protective effect against the toxicity of human Aβ₁₋₄₂ peptide in primary cortical neuron cells, as shown in Table 4 below and exemplified in FIGS. 7 to 12 and 16 to 22. The results clearly show that intoxication by aggregated human amyloid peptide (Aβ₁₋₄₂ 10 μM) is significantly prevented by combinations of the invention, whereas, at those concentrations, the drugs alone have no significant effect on intoxication in the experimental conditions described above.

TABLE 4 Protective effect in Aβ₁₋₄₂ intoxicated primary cortical DRUG COMBINATIONS neuron cells Acamprosate and Ifenprodil + Baclofen and Mexiletine + Baclofen and Trimetazidine + Baclofen and Torasemide + Cinacalcet and Mexiletine + Cinnarizine and Trimetazidine + Trimetazidine and Zonisamide + Levosimendan and Mexiletine + Levosimendan and Ifenprodil + Levosimendan and Trimetazidine + Levosimendan and Moxifloxacin + Mexiletine and Ifenprodil + Moxifloxacin and Baclofen + Moxifloxacin and Cinacalcet + Moxifloxacin and Trimetazidine + Moxifloxacin and Sulfisoxazole + Moxifloxacin and Zonisamide + Torasemide and Sulfisoxazole + Baclofen and Trimetazidine and Torasemide + Baclofen and Cinacalcet and Torasemide + Baclofen and Acamprosate and Torasemide + Sulfisoxazole and Trimetazidine and + Torasemide and Zonisamide Sulfisoxazole and Mexiletine and Torasemide and + Cinacalcet Baclofen and Acamprosate and Torasemide and + Diethylcarbamazine Baclofen and Acamprosate and Torasemide and + Ifenprodil Levosimendan and Baclofen and Trimetazidine + Levosimendan and Aminocaproic acid and + Trimetazidine Levosimendan and Terbinafine and Trimetazidine + Levosimendan and Sulfisoxazole and Trimetazidine +

As exemplified in FIGS. 7 to 12 and 15 to 22, the following drug combinations give particularly interesting protective effects against the toxicity of human Aβ₁₋₄₂ peptide in intoxicated primary cortical neuron cells:

-   -   Acamprosate and Ifenprodil,     -   Baclofen and Mexiletine,     -   Baclofen and Torasemide,     -   Baclofen and Trimetazidine,     -   Cinacalcet and Mexiletine,     -   Cinnarizine and Trimetazidine,     -   Trimetazidine and Zonisamide.     -   Mexiletine and Ifenprodil,     -   Moxifloxacin and Baclofen,     -   Moxifloxacin and Cinacalcet,     -   Moxifloxacin and Trimetazidine,     -   Moxifloxacin and Sulfisoxazole,     -   Moxifloxacin and Zonisamide, and     -   Torasemide and Sulfisoxazole.         II.4. Protection of Neurite Growth Against Aβ₁₋₄₂ Toxicity         Test Compounds and Aβ1-42 Treatment

Primary rat cortical neurons are cultured as described previously.

After 10 days of culture, cells are incubated with drugs. After 1 hour, cells are intoxicated by 2.5 μM of beta-amyloid (1-42; Bachem) in defined medium without BDNF but together with drugs. Cortical neurons are intoxicated for 24 hours. BDNF (10 ng/ml) is used as a positive (neuroprotective) control. Three independent cultures were performed per condition, 6 wells per condition.

Neurite Length

After 24 hours of intoxication, the supernatant is taken off and the cortical neurons are fixed by a cold solution of ethanol (95%) and acetic acid (5%) for 5 min. After permeabilization with 0.1% of saponin, cells are blocked for 2 h with PBS containing 1% fetal calf serum. Then cells are incubated with monoclonal antibody anti microtubule-associated protein 2 (MAP-2; Sigma). This antibody is revealed with Alexa Fluor 488 goat anti-mouse IgG (Molecular Probes). Nuclei of neurons were labeled by a fluorescent marker (Hoechst solution, Sigma).

Per well, 10 pictures are taken using InCell Analyzer™ 1000 (GE Healthcare) with 20× magnification. All pictures are taken in the same conditions. Analysis of the neurite network is done using Developer software (GE Healthcare) in order to assess the total length of neurite network.

Results

The combination of Baclofen and Torasemide induces a significant protective effect against the toxicity of human Aβ₁₋₄₂ peptide (improvement of 531% of neurite networks) in primary cortical neuron cells, as shown in FIG. 23. The results clearly show that intoxication by human amyloid peptide (Aβ₁₋₄₂ 2.5 μM) is significantly prevented by the combination and that, moreover, the combination enhances neurite networks in comparison with the control.

Hence, this combination allows an effective protection of cortical neuron cells and cell neuronal networks against the toxicity of human Aβ₁₋₄₂ peptide. Moreover, such an augmentation of neurite networks confirms the efficacy of such drugs in neurological disorders like spinal cord injury.

III. The Compounds Prevent Toxicity of Human Aβ₂₅₋₃₅ In Vivo

Animals

Male Swiss mice are used throughout the study. Animals are housed in plastic cages, with free access to laboratory chow and water, except during behavioral experiments, and kept in a regulated environment, under a 12 h light/dark cycle (light on at 8:00 a.m.). Behavioral experiments are carried out in a soundproof and air-regulated experimental room, to which mice have been habituated at least 30 min before each experiment.

Amyloid Peptide Preparation and Injection

The Aβ₂₅₋₃₅ peptide and scrambled Aβ₂₅₋₃₅ peptide have been dissolved in sterile bidistilled water, and stored at −20° C. until use. Light microscopic observation indicated that incubating the Aβ₂₅₋₃₅ peptide, but not the scrambled Aβ₂₅₋₃₅ peptide, led to the presence of two types of insoluble precipitates, birefringent fibril-like structures and amorphous globular aggregates. The β-amyloid peptides are then administered intracerebroventricularly (i.c.v.). In brief, each mouse is anesthetized lightly with ether, and a gauge stainless-steel needle is inserted unilaterally 1 mm to the right of the midline point equidistant from each eye, at an equal distance between the eyes and the ears and perpendicular to the plane of the skull. Peptides or vehicle are delivered gradually within approximately 3 s. Mice exhibit normal behavior within 1 min after injection. The administration site is checked by injecting India ink in preliminary experiments. Neither insertion of the needle nor injection of the vehicle have a significant influence on survival, behavioral responses or cognitive functions.

Drug Treatment

On day −1, i.e., 24 h before the Aβ₂₅₋₃₅ peptide injection, drugs, drug combination or the vehicle solution are administered per os by gavage twice daily (at 8:00 am and 6:00 pm).

On day 0 (at 10:00 am), mice are injected i.c.v. with Aβ25-35 peptide or scrambled Aβ25-35 peptide (control) in a final volume of 3 μl (3 mM).

Between day 0 and day 7, drugs, drug combination or the vehicle solution are administered per os by gavage once or twice daily (at 8:00 am and 6:00 pm). One animal group receives donepezil (reference compound—1 mg/kg/day) per os by gavage in a single injection (at 8:00 am). Drugs are solubilized in water and freshly prepared just before each gavage administration.

On day 7, all animals are tested for spontaneous alternation performance in the Y-maze test, an index of spatial working memory.

On day 7 and 8, the contextual long-term memory of the animals is assessed using the step-down type passive avoidance procedure.

On day 8, animals are sacrificed. Their brains are dissected and kept at −80° C. for further analysis.

Positive results are observed in behavioral performances and biochemical assays performed 7 days after Aβ₂₅₋₃₅ peptide i.c.v. injection, notably for the combinations listed in Table 5.

TABLE 5 Results in biochemical and/or behavioral DRUG COMBINATIONS assays Baclofen and Torasemide + Mexiletine and Cinacalcet + Sulfisoxazole and Torasemide + Baclofen and Trimetazidine and Torasemide + Baclofen and Cinacalcet and Torasemide + Baclofen and Acamprosate and Torasemide + Sulfisoxazole and Trimetazidine and + Torasemide and Zonisamide Sulfisoxazole and Mexiletine and Torasemide + and Cinacalcet Baclofen and Acamprosate and + Torasemide and Diethylcarbamazine Baclofen and Acamprosate and Torasemide + and Ifenprodil Levosimendan and Baclofen and Trimetazidine + Levosimendan and Aminocaproic acid and + Trimetazidine Levosimendan and Terbinafine and Trimetazidine + Levosimendan and Sulfisoxazole and + Trimetazidine IV. Compounds Enhanced Behavioral and Cognitive Performances of Intoxicated Animals Animals are intoxicated as in the above section. Spontaneous alternation performances: Y-Maze Test

On day 7, all animals are tested for spontaneous alternation performance in the Y-maze, an index of spatial working memory. The Y-maze is made of grey polyvinylchloride. Each arm is 40 cm long, 13 cm high, 3 cm wide at the bottom, 10 cm wide at the top, and converges at an equal angle. Each mouse is placed at the end of one arm and allowed to move freely through the maze during an 8 min session. The series of arm entries, including possible returns into the same arm, are checked visually. An alternation is defined as entries into all three arms on consecutive occasions. The number of maximum alternations is therefore the total number of arm entries minus two and the percentage of alternation is calculated as (actual alternations/maximum alternations)×100. Parameters include the percentage of alternation (memory index) and total number of arm entries (exploration index). Animals that show extreme behavior (alternation percentage<25% or >85% or number of arm entries<10) are discarded. Usually, this accounts for 0-5% of the animals. This test incidentally serves to analyze at the behavioral level the impact and the amnesic effect induced in mice by the Aβ25-35 injection.

Passive Avoidance Test

The apparatus is a two-compartment (15×20×15 cm high) box with one illuminated with white polyvinylchloride walls and the other darkened with black polyvinylchloride walls and a grid floor. A guillotine door separates each compartment. A 60 W lamp positioned 40 cm above the apparatus lights up the white compartment during the experiment. Scrambled footshocks (0.3 mA for 3 s) could be delivered to the grid floor using a shock generator scrambler (Lafayette Instruments, Lafayette, USA). The guillotine door is initially closed during the training session. Each mouse is placed into the white compartment. After 5 s, the door raises. When the mouse enters the darkened compartment and places all its paws on the grid floor, the door closes and the footshock is delivered for 3 s. The step-through latency, that is, the latency spent to enter the darkened compartment, and the number of vocalizations are recorded. The retention test is carried out 24 h after training. Each mouse is placed again into the white compartment. After 5 s the doors are raised, and the step-through latency and the escape latency, i.e., the time spent to return into the white compartment, are recorded up to 300 s.

Positive results are observed for each for the tested combinations listed in Table 6.

TABLE 6 Passive avoidance Step through Drug Combination Y MAZE test Escape latency latency Baclofen-Torasemide + + + Baclofen-Acamprosate- + + + Torasemide Mexiletine and + + + Cinacalcet Sulfisoxazole and + + + Torasemide V. Compounds of the Invention Improve Neurophysiological Concern of Neurological Diseases

Combination therapies are tested in the in vivo model of Aβ intoxication. Their effects on several parameters which are affected in neurological diseases are assessed:

-   -   Caspase 3 and 9 expression levels, considered an indicator of         apoptosis,     -   Lipid peroxidation, considered a marker for oxidative stress         level,     -   GFAP expression assay, considered a marker of the level of brain         inflammation,     -   Blood-brain barrier integrity, and     -   Overall synapse integrity (synaptophysin ELISA).         Blood-Brain Barrier Integrity

Experimental design for animal intoxication by Aβ is the same as that in part III.

The potential protective effect of the combination therapies on the blood-brain barrier (BBB) integrity is analyzed in mice injected intracerebroventricularly (i.c.v.) with oligomeric amyloid-β25-35 peptide (Aβ25-35) or scrambled Aβ25-35 control peptide (Sc.Aβ), 7 days after injection.

On day 7 after the Aβ₂₅₋₃₅ injection, animals are tested to determine the BBB integrity by using the EB (Evans Blue) method. EB dye is known to bind to serum albumin after peripheral injection and has been used as a tracer for serum albumin.

EB dye (2% in saline, 4 ml/kg) is injected intraperitoneal (i.p.) 3 h prior to the transcardiac perfusion. Mice are then anesthetized with i.p. 200 μl of pre-mix ketamine 80 mg/kg, xylazine 10 mg/kg, and the chest is opened. Mice are perfused transcardially with 250 ml of saline for approximately 15 min until the fluid from the right atrium becomes colorless. After decapitation, the brain is removed and dissected out into three regions: cerebral cortex (left+right), hippocampus (left+right), and diencephalon. Then each brain region is weighed for quantitative measurement of EB-albumin extravasation.

Samples are homogenized in phosphate-buffered saline solution and mixed by vortexing after addition of 60% trichloroacetic acid to precipitate the protein. Samples are cooled at 4° C., and then centrifuged 30 min at 10,000 g, 4° C. The supernatant is measured at 610 nm for absorbance of EB using a spectrophotometer.

EB is quantified as both:

-   -   μg/mg of brain tissue by using a standard curve, obtained by         known concentration of EB-albumin, and     -   μg/mg of protein.

As mentioned in Table 7, combination therapies of the invention are efficient at maintaining BBB integrity when compared with non-treated intoxicated animals.

Overall Synapse Integrity (Synaptophysin ELISA)

Synaptophysin has been chosen as a marker of synapse integrity and is assayed using a commercial ELISA kit (USCN, Ref. E90425Mu). Samples are prepared from hippocampus tissues and homogenized in an extraction buffer specific to as described by the manufacturer and reference literature.

Tissues are rinsed in ice-cold PBS (0.02 pH 7.0-7.2) to remove excess blood thoroughly and weighed before nitrogen freezing and −80° C. storage. Tissues are cut into small pieces and homogenized in 1 ml ice-cold phosphate-buffered saline (PBS) solution with a glass homogenizer. The resulting suspension is sonicated with an ultrasonic cell disrupter or subjected to two freeze-thawing cycles to further break the cell membranes. Then homogenates are centrifugated for 5 min at 5,000 g and the supernatant is assayed immediately.

All samples are assayed in triplicate.

Quantification of proteins is performed with the Pierce BCA (bicinchoninic acid) protein assay kit (Pierce, Ref. #23227) to evaluate extraction performance and allow normalization.

The total protein concentrations are then calculated from standard curve dilutions and serve to normalize ELISA results.

Results (Table 7) show that combination therapies are efficient at maintaining an overall synaptophysin level in the brains of treated animals when compared with the non-treated intoxicated animals.

Oxidative Stress Assay

Mice are sacrificed by decapitation and both hippocampi are rapidly removed, weighed and kept in liquid nitrogen until assayed. After thawing, hippocampi are homogenized in cold methanol (1/10 w/v) and centrifuged at 1,000 g for 5 min and the supernatant is placed in an Eppendorf tube. The reaction volumes of each homogenate are added to FeSO₄ 1 mM, H₂SO₄ 0.25 M, xylenol orange 1 mM and incubated for 30 min at room temperature. After reading the absorbance at 580 nm (A580 1), 10 μl of cumene hydroperoxyde 1 mM (CHP) is added to the sample and incubated for 30 min at room temperature, to determine the maximal oxidation level. The absorbance is measured at 580 nm (A580 2). The level of lipid peroxidation is determined as CHP equivalents (CHPE) according to: CHPE=A580 1/A580 2×[CHP] and expressed as CHP equivalents per weight of tissue and as a percentage of control group data.

Results (Table 7) show that combination therapies are efficient at reducing the overall oxidative stress induced by Aβ in the brains of treated animals when compared with the non-treated intoxicated animals.

Caspase Pathway Induction Assay and GFAP Expression Assay

Mice are sacrificed by decapitation and both hippocampi are rapidly removed, rinsed in ice-cold PBS (0.02 mol/l, pH 7.0-7.2) to remove excess blood thoroughly, weighed and kept in liquid nitrogen until assayed. Tissues are cut into small pieces and homogenized in 1 ml ice-cold PBS with a glass homogenizer. The resulting suspension is sonicated with an ultrasonic cell disrupter or subjected to two freeze-thawing cycles to further break the cell membranes. Then homogenates are centrifugated at 5,000 g for 5 min and the supernatant is assayed immediately.

Experiments are conducted with commercial assays: Caspase-3 (USCN—E90626Mu), Caspase-9 (USCN—E90627Mu), and GFAP (USCN—E90068).

Quantification of proteins is performed with the Pierce BCA (bicinchoninic acid) protein assay kit (Pierce, Ref. #23227) to evaluate extraction performance and allow normalization.

Results (Table 7) show that combination therapies have a positive effect on markers of apoptosis and inflammation in the brains of treated animals when compared with the non-treated intoxicated animals.

TABLE 7 Overall Drug Caspase Oxydative GFAP BBB Synapse Combination pathway stress expression integrity integrity Baclofen- + + + + + Torasemide Baclofen- + + + + + Acamprosate- Torasemide Mexiletine and + + + + + Cinacalcet Sulfisoxazole and + + + + + Torasemide

B) Prevention of Glutamate Toxicity on Neuronal Cells

In this further set of experiments, candidate compounds have been tested for their ability to prevent or reduce the toxic effects of glutamate toxicity on neuronal cells. Glutamate toxicity is involved in the pathogenesis of neurological diseases or disorders such as multiple sclerosis, Alzheimer's disease, amyotrophic lateral sclerosis, Parkinson's disease, Huntington's disease, neuropathies, alcoholism or alcohol withdrawal, or spinal cord injury. The drugs are first tested individually, followed by assays of their combinatorial action.

Methods

The efficacy of drug combinations of the invention is assessed on primary cortical neuron cells. The protocol which is used in these assays is the same as described in section A.I.2 above.

Glutamate Toxicity Assays

The neuroprotective effect of compounds is assessed by quantification of the neurite network (neurofilament immunostaining (NF)) which specifically reveals the glutamatergic neurons.

After 12 days of neuron culture, drugs of the candidate combinations are solved in culture medium (+0.1% DMSO). Candidate combinations are then pre-incubated with neurons for 1 hour before the glutamate injury. One hour after incubation, glutamate is added for 20 min, to a final concentration of 40 μM, in the presence of the candidate combinations, in order to avoid further drug dilutions. At the end of the incubation, the medium is changed for medium with the candidate combination but without glutamate. The culture is fixed 24 hours after glutamate injury. MK801 (Dizocilpinehydrogen maleate, 77086-22-7-20 μM) is used as a positive control.

After permeabilization with saponin (Sigma), cells are blocked for 2 h with PBS containing 10% goat serum, then the cells are incubated with mouse monoclonal primary antibody against neurofilament antibody (NF, Sigma). This antibody is revealed with Alexa Fluor 488 goat anti-mouse lgG.

Nuclei of cells are labeled by a fluorescent marker (Hoechst solution, Sigma), and neurite networks are quantified. Six wells per condition are used to assess neuronal survival in 3 different cultures.

Results

All of the tested drug combinations give a protective effect against glutamate toxicity for cortical neuronal cells. Results are shown in Table 8 below.

As exemplified in FIGS. 24 and 25, combinations of the invention strongly protect neurons from glutamate toxicity under the experimental conditions described above. It is noteworthy that an effective protection is noticed using drug concentrations at which the drugs used alone have no significant or a lower protective effect.

TABLE 8 Neuroprotective effect against Drug Combination glutamate toxicity Baclofen-Torasemide + Baclofen-Acamprosate-Torasemide + Mexiletine and Cinacalcet + Sulfisoxazole and Torasemide +

C) Improvement of Other Disorders Related to Glutamate Excitoxicity Using Combinations of the Invention

The above-mentioned in vitro protective effect against glutamate toxicity of drugs and drug combinations of the invention, combined with the protective effects exemplified herein in several AD models, prompted the inventors to test these drugs and combinations in some models of other diseases in the pathogenesis of which glutamate toxicity is also involved, such as MS, ALS and neuropathic pain.

I) Protective Effect of Combinations in an In Vivo Model of Multiple Sclerosis

A model in which myelin-oligodendrocyte glycoprotein-immunized (MOG-immunized) mice develop chronic progressive EAE is used to demonstrate the beneficial effect of compositions of the invention in multiple sclerosis treatment.

Animals and Chemicals

C57L/6J female mice (8 weeks old) are purchased from Janvier (France); after two weeks of habituation, female mice (10 weeks old) develop chronic paralysis after immunization with MOG (Myelin Oligodendrocyte Glycoprotein) peptide. The experimental encephalomyelitis is induced with the Hooke Kit MOG₃₅₋₅₅/CFA Emulsion PTX (pertussis toxin) for EAE Induction (EK-0110, EK-0115; Hooke Laboratories). The control kit is CK-0115 (Hooke Laboratories).

Experimental Procedure

The experimental encephalomyelitis is induced by following procedure.

On day 0, two subcutaneous injections of 0.1 ml each are performed: one in the upper back of the mouse and one in the lower back. Each injection contains 100 μg of MOG₃₅₋₅₅ peptide (MEVGWYRSPFSRVVHLYRNGK), 200 μg of inactivated Mycobacterium tuberculosis H37Ra and is emulsified in Complete Freund's adjuvant (CFA) (Hooke Laboratories). The emulsion provides antigen needed to expand and differentiate MOG-specific autoimmune T cells.

Two intraperitoneal injections of 500 ng of pertussis toxin in PBS (Hooke kit) are performed 2 hours (Day 0) and 24 hours (Day 1) after the MOG injection. Pertussis toxin enhances EAE development by providing additional adjuvant.

Mice develop EAE 8 days after immunization and stay chronically paralyzed for the duration of the experiment. After the immunization, mice are daily observed for clinical symptoms in a blind procedure. Animals are kept in a conventional pathogen-free facility and all experiments are carried out in accordance with guidelines prescribed by, and are approved by, the standing local committee on bioethics.

Experimental Groups and Drug Treatment:

Groups of female mice as disclosed are homogenized by weight before the immunization:

-   -   Control group: vehicle injection in the same conditions as EAE         mice (from Day −1 to Day 28, placebo is given daily).     -   EAE group: MOG injection (day 0)+pertussis toxin injections (Day         0 and 1)—from Day −1 to Day 28, placebo is given orally daily.     -   EAE+positive control: MOG injection (Day 0)+pertussis toxin         injections (Day 0 and 1)—from Day −1 to Day 28, dexamethazone is         given orally daily.     -   EAE+treatment group: MOG injection (Day 0)+pertussis toxin         injections (Day 0 and 1). The treatments start one day before         immunization and last until Day 28.

The clinical scores are measured at Days 0-5-8-9-12-14-16-19-21-23-26-28.

Statistica software (StatSoft Inc.) is utilized throughout for statistical analysis. ANOVA analysis and Student's t-test are employed to analyze clinical disease scores. P<0.05 is considered significant.

Delay of disease occurrence, clinical score and delay of death have been compared between each group to the reference “immu” group with Kaplan-Meier curves and a Cox model (R package ‘survival’). Resulting p-values are unilateral and test the hypothesis to be better than the reference ‘immu’ group.

The total clinical score is composed of the tail score, the hind limb score, the fore limb score and the bladder score, as described below.

Tail Score

Score = 0 A normal mouse holds its tail erect when moving. Score = 1 If the extremity of the tail is flaccid with a tendency to fall. Score = 2 If the tail is completely flaccid and drags on the table. Hind Limn Score

Score = 0 A normal mouse has an energetic walk and doesn't drag his paws Score = 1 Either one of the following tests is positive: A - Flip test: while holding the tail between thumb and index finger, flip the animal on his back and observe the time it takes to right itself. A healthy mouse will turn itself immediately. A delay suggests hind-limb weakness. B - Place the mouse on the wire cage top and observe as it crosses from one side to the other. If one or both limbs frequently slip between the bars we consider that there is a partial paralysis. Score = 2 Both previous tests are positive. Score = 3 One or both hind limbs show signs of paralysis but some movements are preserved; for example: the animal can grasp and hold on to the underside of the wire cage top for a short moment before letting go. Score = 4 When both hind legs are paralyzed and the mouse drags them when moving. Fore Limb Score

Score = 0 A normal mouse uses its front paws actively for grasping and walking and holds its head erect. Score = 1 Walking is possible but difficult due to a weakness in one or both of the paws, for example, the front paws are considered weak when the mouse has difficulty grasping the underside of the wire top cage. Another sign of weakness is head drooping. Score = 2 When one forelimb is paralyzed (impossibility to grasp and the mouse turns around the paralyzed limb). At this time the head has also lost much of its muscle tone. Score = 3 Mouse cannot move, and food and water are unattainable. Bladder Score

Score = 0 A normal mouse has full control of its bladder. Score = 1 A mouse is considered incontinent when its lower body is soaked with urine.

The global score for each animal is determined by the addition of all of the above-mentioned categories. The maximum score for live animals is 10.

Results: Combination Therapies are Efficient in a MS Model

A significant improvement of global clinical score is observed in “EAE+treatment group” mice, notably for the combinations listed in Table 9.

TABLE 9 Improvement of the global clinical Drug Combination score in EAE animals Baclofen-Torasemide + Baclofen-Acamprosate-Torasemide + Mexiletine and Cinacalcet + Sulfisoxazole and Torasemide + II. Protective Effect of Combinations in Models of ALS

Combination therapies according to the present invention are tested in vitro, in a coculture model, and in vivo, in a mouse model of ALS. Protocols and results are presented in this section.

II.1 Protective Effect Against Glutamate Toxicity in Primary Cultures of Nerve-Muscle Co-Culture

Primary Cocultures of Nerve and Muscle Cells

Human muscle is prepared according to a previously described method from portions of biopsies of healthy patients (44). Muscle cells are established from dissociated cells (10,000 cells per well), plated in gelatin-coated 0.1% in 48-well plates and grown in a proliferating medium consisting of a mix of MEM medium and M199 medium.

Immediately after satellite cell fusion, whole transverse slices of 13-day-old Wistar rat embryos' spinal cords with dorsal root ganglia (DRG) attached are placed on the muscle monolayer, 1 explant per well (in center area). DRG are necessary to achieve a good ratio of innervations. Innervated cultures are maintained in mixed medium. After 24 h in the usual co-culture, neurites are observed growing out of the spinal cord explants. They make contacts with myotubes and induce the first contractions after 8 days. Quickly thereafter, innervated muscle fibers located in proximity to the spinal cord explants are virtually continuously contracting. Innervated fibers are morphologically and spatially distinct from the non-innervated ones and could easily be distinguished from them.

One co-culture is done (6 wells per condition).

Glutamate Injury

On day 27, co-cultures are incubated with candidate compounds or Riluzole one hour before glutamate intoxication (60 μM) for 20 min. Then co-cultures are washed and candidate compounds or Riluzole are added for an additional 48 h. After this incubation time, unfixed cocultures are incubated with α-bungarotoxin coupled with Alexa 488 at a concentration of 500 nmol/L for 15 min at room temperature. Then co-cultures are fixed by PFA for 20 min at room temperature. After permeabilization with 0.1% of saponin, co-cultures are incubated with anti-neurofilament antibody (NF).

These antibodies are detected with Alexa Fluor 568 goat anti-mouse IgG (Molecular Probes). Nuclei of neurons are labeled by a fluorescent marker (Hoechst solution).

Endpoints are (1) Total neurite length, (2) Number of motor units, and (3) Total motor unit area, which are indicative of motor neuron survival and functionality.

For each condition, 2×10 pictures per well are taken using InCell Analyzer™ 1000 (GE Healthcare) with 20× magnification. All the images are taken in the same conditions.

Results

Drugs of the invention effectively protect motor neurons and motor units in the coculture model. Moreover, an improvement of the protection is noticed when drugs are used in combination for the drug combinations listed in Table 10.

TABLE 10 Protective effect against glutamate intoxication in muscle/nerve Drug Combination co-cultures Baclofen-Torasemide + Baclofen-Acamprosate-Torasemide + Mexiletine and Cinacalcet + Sulfisoxazole and Torasemide + II.2—Combination Therapies are Efficient in ALS Mouse Model

Experiments are performed on male mice. Transgenic male B6SJL-Tg(SOD1)2Gur/J mice and their controls (respectively, SN2726 and SN2297, from Jackson Laboratories, Ben Harbor, USA and distributed by Charles River, France) are chosen for this set of experiments to mimic ALS.

Diseased mice express the SOD1-G93A transgene, designed with a mutant human SOD1 gene (a single amino acid substitution of glycine to alanine at codon 93) driven by its endogenous human SOD1 promoter. Control mice express the control human SOD1 gene.

Drug Administration

Mice are dosed with candidate drug treatment diluted in vehicle from the 60th day after birth till death. Diluted solutions of drug candidates are prepared with water at room temperature just before the beginning of the administration.

In Drinking Water

Riluzole is added in drinking water at a final concentration of 6 mg/ml (adjusted to each group's mean body weight) in 5% cyclodextrin. As a mouse drinks about 5 ml/day, the estimated administrated dose is 30 mg/kg/day, which is a dose that was shown to increase the survival of mice.

-   -   Cyclodextrin is used as vehicle at the final concentration of         5%, diluted in water at room temperature from stock solution         (cyclodextrin 20%).

Oral Administration (Per Os)

-   -   Drug combinations are administrated per os, daily.     -   Cyclodextrin is used as vehicle at the final concentration of         5%, diluted in water at room temperature from stock solution         (cyclodextrin 20%).         Clinical Observation

The clinical observation of each mouse is performed daily, from the first day of treatment (60 days of age) until death (or sacrifice). Clinical observation consists of studying behavioral tests: onset of paralysis, “loss of splay”, “loss of righting reflex”, and general gait observation:

-   -   Onset of paralysis: The observation consists of paralysis         observation of each limb. Onset of paralysis corresponds to the         day of the first signs of paralysis.     -   The loss of splay test consists of tremors or shaking         notification and the position of the hind limbs (hanging or         splaying out) when the mouse is suspended by the tail.     -   The loss of righting reflex test evaluates the ability of the         mouse to right itself within 30 sec of being turned on either         side. The righting reflex is lost when the mouse is unable to         right itself. The loss of righting reflex determines the end         stage of disease: the mouse unable to right itself is         euthanized.         Results: Combination Therapies are Efficient in ALS In Vivo         Model

An improvement of the disease is observed for the diseased animals treated with the drugs and drug combinations of the invention. Notably, drug combinations listed in Table 11 efficiently improve the clinical scores of these animals during the different stages of the disease.

TABLE 11 Effect on clinical score in diseased Drug Combination animals Baclofen-Torasemide + Baclofen-Acamprosate-Torasemide + Mexiletine and Cinacalcet + Sulfisoxazole and Torasemide + III) Protective Effect of Combinations of the Invention in Oxaliplatin-Induced Neuropathy as an In Vivo Model for Neuropathic Pain

Combinatorial therapies of the present invention are tested in vivo, in suitable models of peripheral neuropathy, i.e., an acute model of oxaliplatin-induced neuropathy and a chronic model of oxaliplatin-induced neuropathy. The animals, protocols and results are presented in this section.

Animal Husbandry

Sprague-Dawley rats (CERJ, France), weighing 150-175 g at the beginning of the experimental oxaliplatin treatment (D₀) are used. Animals are housed in a limited-access animal facility in a temperature (19.5° C.-24.5° C.) and relative humidity (45-65%) controlled room with a 12 h—light/dark cycle, with ad libitum access to standard pelleted laboratory chow and water throughout the study. Animals are housed 4 or 5 per cage and a one week-acclimation period is observed before any testing.

Experimental Design

The five following groups of rats are used in all experiments:

Control Groups

Group 1: Vehicle of oxaliplatin (distilled water), i.p./Vehicle of candidate combination(s) (distilled water), p.o. daily.

Group 2: Oxaliplatin (distilled water), i.p./Vehicle of candidate combination(s) (distilled water), p.o. daily.

Group 3: Oxaliplatin 3 mg/kg i.p./single drug in distilled water, p.o. daily×9.

Tested Composition Groups

Group 4: Oxaliplatin 3 mg/kg i.p./candidate combination(s) in distilled water, p.o. daily×9.

Group 5: Oxaliplatin 3 mg/kg i.p./Gabapentin (100 mg/kg) in distilled water, p.o. on testing days (i.e., D₁ & D₈).

Vehicle and test items are delivered daily from D1 to D7 (the day before the last testing day), whereas Gabapentin is administered on testing days (120 minutes before the test).

All treatments are administered in a coded and random order when possible. Doses are expressed in terms of free active substance.

Neuropathy Induction

Acute neuropathy is induced by a single intraperitoneal injection of oxaliplatin (3 mg/kg).

Chronic peripheral neuropathy is induced by repeated intraperitoneal injections of oxaliplatin (3 mg/kg, i.p.) on days 0, 2, 4 and 7 (CD=12 mg/kg, i.p.). Chronic neuropathy in humans is cumulative as well and is most commonly seen in patients who have received total doses of oxaliplatin> or =540 mg/m², which corresponds to ˜15 mg/kg as a cumulative dose in rats (Cersosimo, R. J., 2005).

The oxaliplatin-induced painful neuropathy in rats reproduces the pain symptoms in oxaliplatin-treated patients.

-   -   The thermal hyperalgesia is the earliest symptom. It can be         measured with the acetone test or with the tail-immersion test.     -   The mechanical hyperalgesia appears later. It can be quantified         with the Von Frey test or the paw pressure test.         Animal Dosing and Testing

All drug combinations are administered from the day before the first intraperitoneal injection of oxaliplatin 3 mg/kg (D1) and orally daily until D7. During the testing days (i.e., D1 and D7), the drug combinations are administered after the test. Animals from the reference-treated group (Gabapentin) are dosed only during the testing days.

Acetone Test

Cold allodynia is assessed using the acetone test by measuring the responses to thermal non-nociceptive stimulation on D1 (around 24 h after the first injection of oxaliplatin 3 mg/kg) (acute effect of oxaliplatin) and D8 (chronic effect of oxaliplatin).

In the acetone test, latency of hindpaw withdrawal is measured after application of a drop of acetone to the plantar surface of both hindpaws (reaction time) and the intensity of the response is scored (cold score). Reaction time to the cooling effect of acetone is measured within 20 sec (cut-off) after acetone application. Responses to acetone are also graded to the following 4-point scale: 0 (no response); 1 (quick withdrawal, flicking of the paw); 2 (prolonged withdrawal or marked flicking of the paw); and 3 (repeated flicking of the paw with licking or biting).

For each experimental group, results are expressed as:

-   -   The reaction time, defined as the time expressed in sec required         to elicit paw reaction (mean of 6 measurements for each rat         together ±SEM).     -   The cumulative cold score, defined as the sum of the 6 scores         for each rat together ±SEM. The minimum score is 0 (no response         to any of the 6 trials) and the maximum possible score is 18         (repeated flicking and licking or biting of paws on each of the         six trials).         Statistical Analyses

Student's t-test, unilateral, type 3 is performed. The significance level is set as p<0.05; all the groups are compared to the diseased+vehicle group (oxaliplatin-treated group). Means and standard error means are shown in the figures.

Results

Oxaliplatin induced a significant decrease in reaction time of paw withdrawal after acetone application (diseased group+vehicle) during the time course. This decrease is progressive and significant from day 1 (acute model of oxaliplatin-induced neuropathy) to day 8 (chronic model) as compared to the vehicle group.

Anti-Allodynic Effect in Acute Model of Oxaliplatin-Induced Neuropathy

The drug combinations tested in the acute model of oxaliplatin-induced neuropathy are assessed with the acetone test. Table 12 presents drug combinations (Group 4) which induce a significant decrease in the cumulative cold score and a significant increase of reaction time as compared to the oxaliplatin-vehicle treated group (Group 2). In conclusion, these drug combinations protect animals from acute neuropathy induced by oxaliplatin.

TABLE 12 Variation of the Reaction Drug combinations tested in cold score time acute model of neuropathy compared to compared to Anti-allodynic (Group 4) Group 2 Group 2 effect Baclofen-Torasemide decrease increase + Baclofen-Acamprosate- decrease increase + Torasemide Mexiletine and Cinacalcet decrease increase + Sulfisoxazole and decrease increase + Torasemide + = anti-allodynic effect obtained in Group 4 of rats, following analysis of the cumulative cold scores and analysis of the reaction time in acetone tests, in acute oxaliplatin-induced model.

Anti-Allodynic Effect in Chronic Model of Oxaliplatin-Induced Neuropathy

The drug combinations used in the chronic model of oxaliplatin-induced neuropathy are assessed with the acetone test.

Table 13 presents drug combinations for which the reaction time and the cold score in the acetone test measured in the Group 4 (animals treated with drug combinations and oxaliplatin) are respectively significantly increased and decreased after the treatment in the chronic model of neuropathy compared to the oxaliplatin-vehicle treated group (Group 2). In conclusion, these drug combinations protect animals from chronic neuropathy induced by oxaliplatin.

TABLE 13 Drug combinations Variation of the Reaction tested in cold score time Chronic model of compared to compared to Anti-allodynic neuropathy (Group 4) Group 2 Group 2 effect Baclofen-Torasemide decrease increase + Baclofen-Acamprosate- decrease increase + Torasemide Mexiletine and decrease increase + Cinacalcet Sulfisoxazole and decrease increase + Torasemide + = anti-allodynic effect obtained in Group 4 of rats, following analysis of the cumulative cold scores and analysis of the reaction time in acetone tests, in chronic oxaliplatin-induced model. IV) Baclofen-Torasemide Based Compositions Promote Nerve Regeneration in Non-Intoxicated Cells

Neurotrophic Effects of Baclofen-Torasemide Combination In Vitro

Neurite Length Assay

Neurite growth evaluation within 10-day-old cultures of rat cortical cells was performed using MAP-2 antibodies as mentioned in section A) 11.4, with the exception that cells have not been exposed to any toxin. 10-day-old cell cultures were incubated with the drugs for 1 day before the assay.

Results

As shown in FIG. 28, the Baclofen-Torasemide combination exhibits a significant neurotrophic effect (+11%), whereas the individual drugs, when used alone, do not have any substantial neurotrophic effect. Indeed, a significant increase in total neurite length within the neuronal network (MAP2-2 labeling) is observed upon exposure to the Baclofen-Torasemide combination (400 nM and 80 nM, respectively). Noteworthily, neither the combination nor the drugs alone have an effect on the number of neurons, thereby stressing that this increase in the neurite network is related to an extension of existing neurites and to the promotion of de novo neuronal cell extensions.

These results confirm that the Baclofen-Torasemide combination is efficient at supporting axon extension and thus is efficient at treating spinal cord injuries and other nerve injuries. It also confirms that the combination is efficient at treating inherited neuropathies comprising either axonal, demyelinating, or both axonal and demyelinating components. Indeed, it should be considered that demyelination causes a destabilization of the axon which results in axonal degeneration observed even in the neuropathies considered to be mainly of the demyelinating form.

Baclofen-Torasemide Based Compositions are Efficient at Promoting Nerve Regeneration In Vivo

Sciatic nerve crush is widely accepted as a valid model for peripheral nerve injury and the assessment of nerve regeneration. In this model, nerve damage results in rapid disruption of nerve function as evidenced by the measurement of the evoked muscle action potential (CMAP) generated through the stimulation of the injured sciatic nerve.

Nerve injury is characterized by a lower nerve conduction of the signal that results from an increased latency in generation of CMAP and an impaired strength of action potential resulting in decreased amplitude and duration.

Usually, the first signs of recovery of nerve function occur within 2 weeks, and, by week 4 post-lesioning, a significant remyelination of the regenerated axons is observed in the sciatic nerve by histology (45).

Nerve Crush

Mice were anesthetized using isoflurane (2.5 to 3% in air). The right thigh was then shaved and the sciatic nerve exposed at mid-thigh level and crushed at 5 mm proximal to the bifurcation of the sciatic nerve. The nerve were crushed for 10 s twice with a microforceps (Holtex, reference P35311) with a 90° rotation between each crush. For sham-operated animals, sciatic nerves were exposed but not crushed. Finally, the skin incision was secured with wound clips. The day of the crush is considered day 0.

Dosage Schedule

The day of the crush, the first administration of compounds was performed 30 min after the crush.

Compounds were then after administered twice daily, from the day after the crush for 42 days. Within a single day, drug administrations were spaced by at least 6 hours.

On test days (days 7 and 30) mice were administered 1 h30 before the test.

The volume of administration was 10 ml/kg, in 0.25% DMSO/sterile water.

Dose 1 (bid) Dose 2 (bid) Dose 3 (bid) Baclofen (+/−)  3 mg/kg  3 mg/kg  3 mg/kg Torasemide 25 μg/kg 100 μg/kg 400 μg/kg Electromyography Measures

Electrophysiological recordings were performed using a Keypoint electromyograph (EMG) (Medtronic, France) on Day 7 and Day 30. Mice were anesthetized by 2.5-3% isoflurane in air. Subcutaneous monopolar needle electrodes were used for both stimulation and recording. Supramaximal (12.8 mA) square wave pulses of 0.2 ms duration were used to stimulate the sciatic nerve. The right sciatic nerve (ipsilateral) was stimulated with single pulse applied at the sciatic notch. CMAP was recorded by needle electrodes placed at the gastrocnemius muscle. The onset (latency) of CMAP signal expressed in milliseconds is used to estimate the nerve conduction velocity. Latency thus reflects the degree of myelinization of the axons. The amplitude of the action (μV) potential was also determined, which reflects the level of denervation and reinnervation of muscles. The amplitude of CMAP is currently given as proportional to the number of regenerated motor axons. Duration of the evoked muscle potential was also determined. Amplitude and duration of the evoked muscle potential are more related to muscle reinnervation. Latency and amplitude are more generally recognized as the most important endpoints when dealing with nerve regeneration. Data were analyzed with a bilateral, type 3, Student's t-test; significant level was set at p<0.05.

Results

Baclofen-Torasemide combinations are efficient, at all the tested doses, at significantly improving the time latency of the signal when compared with vehicle-treated animals, and this as soon as the seventh day from the nerve injury (FIG. 29A). A significant difference is still observed at the 30^(th) day from the nerve crush, when the beginning of a spontaneous recovery is usually observed.

A statistically significant improvement in the amplitude of the signal is also observed for Dose 3 on the 30^(th) day from the nerve crush (FIG. 29B). Such an improvement is also observed, but to a lesser extent, for Doses 1 and 2. Similar results are observed when measuring the duration of the signal.

Altogether, these in vivo results show the efficiency of the Baclofen-Torasemide combination at promoting nerve regeneration through remyelinization and muscle reinnervation. Hence, in vivo experimental data confirm the neurotrophic effects of Baclofen-Torasemide observed in vitro and their usefulness in correcting neuropathies where nerves of the peripheral nervous system are damaged (i.e., neuropathies as defined in the specification) and also spinal cord injury.

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The invention claimed is:
 1. A method of promoting nerve or neuron regeneration in a subject suffering from a nerve injury selected from neuropraxia, axonotmesis or neurotmesis, or from a neuropathy caused by direct physical nerve injury or Charcot-Marie-Tooth (CMT) disease, comprising administering to said subject torasemide and baclofen, or salts, prodrugs, derivatives, or sustained release formulations thereof.
 2. The method of claim 1, which further comprises administering a pharmaceutically acceptable carrier or excipient.
 3. The method of claim 1, comprising administering simultaneously, separately or sequentially torasemide and baclofen to the subject.
 4. The method of claim 1, comprising administering less than 4 mg of torasemide.
 5. The method of claim 1, comprising administering less than 150 mg of baclofen.
 6. The method of claim 5, comprising administering less than 50 mg of baclofen. 